diff --git "a/S3-val.txt" "b/S3-val.txt"
new file mode 100644--- /dev/null
+++ "b/S3-val.txt"
@@ -0,0 +1,56797 @@
+Properties S-CONPRI
+like O
+macro- O
+and O
+microstructure S-CONPRI
+, O
+mechanical B-CONPRI
+properties E-CONPRI
+like O
+hardness S-PRO
+and O
+its O
+course O
+in O
+the O
+layers O
+, O
+high-cycle O
+fatigue S-PRO
+resistance O
+in O
+bending S-MANP
+and O
+fatigue B-PRO
+damage E-PRO
+mechanisms O
+were O
+investigated O
+with O
+the O
+emphasis O
+on O
+fatigue S-PRO
+crack O
+initiation O
+process S-CONPRI
+evaluated O
+using O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+. O
+
+
+The O
+results O
+indicated O
+that O
+surface S-CONPRI
+additive S-MATE
+laser O
+welded S-MANP
+layers O
+of O
+a O
+high O
+quality S-CONPRI
+can O
+be S-MATE
+reached O
+. O
+
+
+On O
+the O
+other O
+hand O
+, O
+some O
+drop O
+of O
+fatigue S-PRO
+resistance O
+and O
+endurance B-PRO
+limit E-PRO
+was O
+observed O
+, O
+affected O
+by O
+surface B-CONPRI
+defects E-CONPRI
+– O
+small O
+welding S-MANP
+imperfections S-CONPRI
+Ti-6Al-4V O
+and O
+AlSi5 S-MATE
+wires O
+were O
+used O
+for O
+wire B-MANP
+and I-MANP
+arc I-MANP
+additive I-MANP
+manufacturing E-MANP
+using O
+the O
+direct O
+current O
+cold B-MANP
+metal I-MANP
+transfer E-MANP
+welding O
+. O
+
+
+Ti B-MATE
+alloy E-MATE
+was O
+deposited O
+first O
+, O
+and O
+then O
+Al B-MATE
+alloy E-MATE
+was O
+deposited O
+on O
+the O
+Ti S-MATE
+layer S-PARA
+. O
+
+
+A O
+small O
+amount O
+of O
+Ti B-MATE
+alloy E-MATE
+was O
+melted S-CONPRI
+when O
+the O
+first O
+layer S-PARA
+of O
+Al B-MATE
+alloy E-MATE
+was O
+deposited O
+due O
+to O
+the O
+low O
+heat S-CONPRI
+input O
+. O
+
+
+A O
+component S-MACEQ
+composed O
+of O
+Ti/Al O
+dissimilar B-MATE
+alloys E-MATE
+can O
+be S-MATE
+produced O
+. O
+
+
+The O
+interface S-CONPRI
+layer O
+between O
+the O
+Ti S-MATE
+and O
+Al B-MATE
+alloys E-MATE
+included O
+a O
+continuous O
+layer S-PARA
+and O
+a O
+discontinuous O
+layer S-PARA
+. O
+
+
+The O
+continuous O
+layer S-PARA
+was O
+composed O
+of O
+Ti7Al5Si12 S-MATE
+, O
+and O
+the O
+discontinuous O
+layer S-PARA
+consisted O
+of O
+Ti S-MATE
+( O
+Al1-xSix O
+) O
+3 O
+. O
+
+
+Element S-MATE
+Si O
+was O
+rich O
+in O
+the O
+continuous O
+layer S-PARA
+. O
+
+
+The O
+hardness S-PRO
+and O
+modulus O
+of O
+the O
+interface S-CONPRI
+layer O
+were O
+between O
+those O
+of O
+Al S-MATE
+and O
+Ti B-MATE
+alloys E-MATE
+. O
+
+
+The O
+average S-CONPRI
+tensile O
+strength S-PRO
+of O
+the O
+component S-MACEQ
+was O
+79 O
+MPa S-CONPRI
+. O
+
+
+The O
+fracture S-CONPRI
+located O
+at O
+the O
+interface S-CONPRI
+layer O
+. O
+
+
+A O
+finite B-CONPRI
+element I-CONPRI
+model E-CONPRI
+is O
+developed O
+to O
+calculate O
+the O
+heat B-CONPRI
+propagation E-CONPRI
+of O
+a O
+circular O
+thin-walled B-APPL
+component E-APPL
+fabricated S-CONPRI
+in O
+gas B-MANP
+metal I-MANP
+arc I-MANP
+welding E-MANP
+based O
+additive B-MANP
+manufacturing E-MANP
+. O
+
+
+The O
+heat B-CONPRI
+evolution E-CONPRI
+, O
+thermal B-PARA
+cycle E-PARA
+feature S-FEAT
+, O
+and O
+temperature B-PARA
+gradient E-PARA
+in O
+molten B-CONPRI
+pool E-CONPRI
+and O
+deposited B-CHAR
+layers E-CHAR
+are O
+revealed O
+. O
+
+
+The O
+temperature S-PARA
+simulations S-ENAT
+at O
+some O
+locations O
+are O
+in O
+agreement O
+with O
+measured O
+values O
+from O
+thermocouples S-MACEQ
+. O
+
+
+As S-MATE
+the O
+deposition B-MANP
+process E-MANP
+proceeds O
+, O
+the O
+high-temperature O
+regions O
+of O
+the O
+substrate S-MATE
+and O
+molten B-CONPRI
+pool E-CONPRI
+increase O
+. O
+
+
+The O
+temperature B-PARA
+gradient E-PARA
+in O
+the O
+molten B-CONPRI
+pool E-CONPRI
+decreases O
+with O
+the O
+increasing O
+deposition S-CONPRI
+height O
+. O
+
+
+The O
+heat B-CONPRI
+dissipation E-CONPRI
+condition O
+in O
+the O
+molten B-CONPRI
+pool E-CONPRI
+of O
+current O
+layer S-PARA
+tightly O
+depends O
+on O
+the O
+deposition B-PARA
+direction E-PARA
+of O
+fore O
+layer S-PARA
+. O
+
+
+At O
+the O
+deposition S-CONPRI
+ending O
+moment O
+, O
+the O
+heat B-CONPRI
+conduction E-CONPRI
+in O
+the O
+axial O
+direction O
+is O
+the O
+predominant O
+heat B-CONPRI
+dissipation E-CONPRI
+orientation O
+, O
+whereas O
+the O
+circumferential O
+orientation S-CONPRI
+becomes O
+the O
+main O
+heat B-CONPRI
+dissipation E-CONPRI
+direction O
+in O
+the O
+top O
+layers O
+. O
+
+
+An O
+automated O
+arc-welding-based B-MANP
+additive I-MANP
+manufacturing E-MANP
+system O
+was O
+reported O
+. O
+
+
+Integrated O
+additive S-MATE
+and O
+subtractive B-MANP
+manufacturing E-MANP
+methodology S-CONPRI
+was O
+developed O
+. O
+
+
+Deposition B-PARA
+paths E-PARA
+and O
+welding S-MANP
+parameters S-CONPRI
+were O
+automatically O
+generated O
+. O
+
+
+User O
+interface S-CONPRI
+using O
+only O
+CAD B-ENAT
+models E-ENAT
+as S-MATE
+inputs O
+was O
+developed O
+. O
+
+
+Arc B-MANP
+welding E-MANP
+has O
+been O
+widely O
+explored O
+for O
+additive B-MANP
+manufacturing E-MANP
+of O
+large O
+metal S-MATE
+components S-MACEQ
+over O
+the O
+last O
+three O
+decades O
+due O
+to O
+its O
+lower O
+capital B-CONPRI
+cost E-CONPRI
+, O
+an O
+unlimited O
+build B-PARA
+envelope E-PARA
+, O
+and O
+higher O
+deposition B-PARA
+rates E-PARA
+. O
+
+
+Although O
+significant O
+improvements O
+have O
+been O
+made O
+, O
+an O
+arc B-MANP
+welding E-MANP
+process O
+has O
+yet O
+to O
+be S-MATE
+incorporated O
+in O
+a O
+commercially O
+available O
+additive B-MACEQ
+manufacturing I-MACEQ
+system E-MACEQ
+. O
+
+
+The O
+next O
+step S-CONPRI
+in O
+exploiting O
+“ O
+true O
+” O
+arc-welding-based B-MANP
+additive I-MANP
+manufacturing E-MANP
+is O
+to O
+develop O
+the O
+automation S-CONPRI
+software O
+required O
+to O
+produce O
+CAD-to-part S-CONPRI
+capability O
+. O
+
+
+This O
+study O
+focuses O
+on O
+developing O
+a O
+fully O
+automated O
+system O
+using O
+robotic O
+gas B-MANP
+metal I-MANP
+arc I-MANP
+welding E-MANP
+to O
+additively B-MANP
+manufacture E-MANP
+metal O
+components S-MACEQ
+. O
+
+
+The O
+system O
+contains O
+several O
+modules O
+, O
+including O
+bead B-CONPRI
+modelling E-CONPRI
+, O
+slicing S-CONPRI
+, O
+deposition B-CONPRI
+path I-CONPRI
+planning E-CONPRI
+, O
+weld S-FEAT
+setting O
+, O
+and O
+post-process B-MANP
+machining E-MANP
+. O
+
+
+Among O
+these O
+modules O
+, O
+bead B-CONPRI
+modelling E-CONPRI
+provides O
+the O
+essential O
+database S-ENAT
+for O
+process B-CONPRI
+control E-CONPRI
+, O
+and O
+an O
+innovative O
+path B-ENAT
+planning E-ENAT
+strategy O
+fulfils O
+the O
+requirements O
+of O
+the O
+automated O
+system O
+. O
+
+
+Finally O
+, O
+a O
+thin-walled B-MACEQ
+aluminium I-MACEQ
+structure E-MACEQ
+has O
+been O
+fabricated S-CONPRI
+automatically O
+using O
+only O
+a O
+CAD B-ENAT
+model E-ENAT
+as S-MATE
+the O
+informational O
+input O
+to O
+the O
+system O
+. O
+
+
+This O
+exercise O
+demonstrates O
+that O
+the O
+developed O
+system O
+is O
+a O
+significant O
+contribution O
+towards O
+the O
+ultimate O
+goal O
+of O
+producing O
+a O
+practical O
+and O
+highly O
+automated O
+arc-welding-based B-MANP
+additive I-MANP
+manufacturing E-MANP
+system O
+for O
+industrial S-APPL
+application O
+. O
+
+
+Laser B-MANP
+additive I-MANP
+manufacturing E-MANP
+titanium O
+alloy S-MATE
+40 O
+mm S-MANP
+thick O
+plate O
+can O
+obtain O
+full O
+penetration B-CONPRI
+joint E-CONPRI
+by O
+EBW S-MANP
+. O
+
+
+In O
+fusion B-CONPRI
+zone E-CONPRI
+, O
+due O
+to O
+acicular O
+α′ O
+formation O
+, O
+the O
+microhardness S-CONPRI
+is O
+higher O
+than O
+base B-MATE
+metal E-MATE
+and O
+heat B-CONPRI
+affected I-CONPRI
+zone E-CONPRI
+. O
+
+
+All O
+tensile S-PRO
+samples S-CONPRI
+fail O
+in O
+base B-MATE
+metal E-MATE
+. O
+
+
+The O
+L-joint S-FEAT
+shows O
+higher O
+strength S-PRO
+but O
+lower O
+ductility S-PRO
+than O
+T-joint S-FEAT
+. O
+
+
+Individually O
+fabrication S-MANP
+parts O
+by O
+laser B-MANP
+additive I-MANP
+manufacturing E-MANP
+( O
+LAM S-MANP
+) O
+and O
+then O
+jointing O
+them O
+together O
+through O
+electron B-MANP
+beam I-MANP
+welding E-MANP
+( O
+EBW S-MANP
+) O
+is O
+a O
+viable O
+way O
+for O
+manufacturing S-MANP
+large O
+components S-MACEQ
+with O
+reduction S-CONPRI
+of O
+internal B-PRO
+stress E-PRO
+. O
+
+
+For O
+investigating O
+the O
+microstructure S-CONPRI
+and O
+mechanical B-CONPRI
+property E-CONPRI
+of O
+EBW S-MANP
+joint O
+along O
+longitudinal O
+and O
+transverse O
+direction O
+in O
+LAMed O
+component S-MACEQ
+, O
+two O
+LAMed O
+Ti–6.5Al–3.5Mo–1.5Zr–0.3Si S-MATE
+plates O
+were O
+successfully O
+welded S-MANP
+without O
+defects S-CONPRI
+. O
+
+
+Results O
+show O
+that O
+the O
+microstructure S-CONPRI
+of O
+base B-MATE
+metal E-MATE
+( O
+BM S-MATE
+) O
+is O
+a O
+typical O
+basket-weave B-CONPRI
+morphology E-CONPRI
+that O
+exhibits O
+lamellar S-CONPRI
+α O
+within O
+β O
+matrix O
+. O
+
+
+In O
+heat B-CONPRI
+affected I-CONPRI
+zone E-CONPRI
+( O
+HAZ S-CONPRI
+) O
+, O
+the O
+part O
+of O
+primary O
+α O
+transforms O
+to O
+β O
+with O
+the O
+some O
+very O
+fine O
+lamellar S-CONPRI
+αs O
+precipitates S-MATE
+out O
+. O
+
+
+Due O
+to O
+the O
+fast O
+solidification B-PARA
+rate E-PARA
+, O
+a O
+large O
+number O
+of O
+acicular O
+α′ O
+forms O
+in O
+fusion B-CONPRI
+zone E-CONPRI
+( O
+FZ S-CONPRI
+) O
+, O
+leading O
+to O
+the O
+highest O
+microhardness S-CONPRI
+. O
+
+
+All O
+tensile S-PRO
+samples S-CONPRI
+fail O
+in O
+BM S-MATE
+region O
+with O
+the O
+fracture S-CONPRI
+type O
+of O
+intergranular O
+dimpled O
+fracture S-CONPRI
+. O
+
+
+Compared O
+with O
+the O
+T-joint S-FEAT
+, O
+the O
+L-joint S-FEAT
+shows O
+higher O
+ultimate B-PRO
+tensile I-PRO
+strength E-PRO
+and O
+yield B-PRO
+strength E-PRO
+, O
+but O
+lower O
+elongation S-PRO
+and O
+reduction B-CHAR
+of I-CHAR
+area E-CHAR
+due O
+to O
+the O
+morphology S-CONPRI
+of O
+columnar B-PRO
+grains E-PRO
+and O
+the O
+strong O
+texture S-FEAT
+of O
+β O
+< O
+010 O
+> O
+parallel O
+to O
+the O
+deposition B-PARA
+direction E-PARA
+. O
+
+
+In O
+Laser-based B-MANP
+Manufacturing E-MANP
+, O
+the O
+configuration S-CONPRI
+of O
+process B-CONPRI
+parameters E-CONPRI
+aims O
+to O
+maintain O
+quality S-CONPRI
+measures O
+within O
+specific O
+boundaries S-FEAT
+and O
+it O
+is O
+obtained O
+through O
+experimentation O
+. O
+
+
+The O
+idea O
+developed O
+and O
+presented O
+in O
+this O
+paper O
+concerns O
+the O
+prediction S-CONPRI
+of O
+the O
+performance S-CONPRI
+of O
+adaptive B-CONPRI
+control E-CONPRI
+policies O
+, O
+based O
+on O
+process B-CONPRI
+modeling E-CONPRI
+. O
+
+
+Two O
+examples O
+of O
+Laser-based B-MANP
+Manufacturing E-MANP
+are O
+deployed O
+in O
+order O
+to O
+verify O
+the O
+response O
+of O
+adaptive B-CONPRI
+control E-CONPRI
+algorithms O
+through O
+empirical S-CONPRI
+design S-FEAT
+, O
+Laser B-MANP
+welding E-MANP
+and O
+Laser-based B-MANP
+Additive I-MANP
+Manufacturing E-MANP
+processes O
+. O
+
+
+The O
+penetration B-PARA
+depth E-PARA
+has O
+been O
+utilized O
+as S-MATE
+the O
+quality S-CONPRI
+criterion O
+of O
+the O
+adaptive B-CONPRI
+control E-CONPRI
+loop O
+for O
+both O
+processes S-CONPRI
+. O
+
+
+The O
+solidification B-CONPRI
+phase E-CONPRI
+has O
+also O
+been O
+examined O
+. O
+
+
+Dissolved O
+oxygen S-MATE
+in O
+weld B-CONPRI
+zone E-CONPRI
+leads O
+to O
+distinct O
+microstructures S-MATE
+from O
+base B-MATE
+metal E-MATE
+after O
+annealing S-MANP
+. O
+
+
+The O
+repaired O
+specimens O
+have O
+lower O
+plasticity S-PRO
+and O
+slightly O
+higher O
+strength S-PRO
+than O
+base B-MATE
+metal E-MATE
+. O
+
+
+Columnar B-CONPRI
+grain I-CONPRI
+boundary E-CONPRI
+α O
+phases O
+in O
+weld B-CONPRI
+zone E-CONPRI
+are O
+the O
+earliest O
+microcracks S-CONPRI
+nucleation O
+sites O
+. O
+
+
+Gas B-MANP
+tungsten I-MANP
+arc I-MANP
+welding E-MANP
+was O
+used O
+to O
+repair O
+the O
+laser S-ENAT
+additive B-MANP
+manufactured E-MANP
+Ti-5Al-5Mo-5V-1Cr-1Fe O
+( O
+Ti-55511 O
+) O
+alloy S-MATE
+with O
+a O
+subsequent O
+triplex O
+annealing B-MANP
+treatment E-MANP
+. O
+
+
+The O
+tensile B-PRO
+properties E-PRO
+of O
+heat S-CONPRI
+treated O
+specimens O
+containing O
+of O
+different O
+proportions O
+of O
+weld B-CONPRI
+zone E-CONPRI
+were O
+designed S-FEAT
+to O
+evaluate O
+the O
+influence O
+of O
+weld B-CONPRI
+zone E-CONPRI
+on O
+tensile B-PRO
+properties E-PRO
+of O
+the O
+alloy S-MATE
+. O
+
+
+Microstructures S-MATE
+, O
+microhardness S-CONPRI
+and O
+tensile B-CHAR
+tests E-CHAR
+were O
+performed O
+to O
+study O
+the O
+mechanical B-CONPRI
+properties E-CONPRI
+and O
+fracture S-CONPRI
+behaviors O
+of O
+the O
+specimens O
+. O
+
+
+Results O
+show O
+that O
+dissolved O
+oxygen S-MATE
+in O
+the O
+weld B-CONPRI
+zone E-CONPRI
+has O
+a O
+strong O
+influence O
+on O
+increasing O
+the O
+number O
+of O
+α O
+phase B-CONPRI
+nucleation I-CONPRI
+sites E-CONPRI
+that O
+can O
+lead S-MATE
+to O
+different O
+αp O
+morphologies S-CONPRI
+in O
+the O
+base B-MATE
+metal E-MATE
+and O
+weld B-CONPRI
+zone E-CONPRI
+. O
+
+
+These O
+different O
+αp O
+can O
+lead S-MATE
+to O
+distinct O
+microstructures S-MATE
+after O
+triplex O
+annealing B-MANP
+treatment E-MANP
+but O
+with O
+similar O
+α O
+volume B-PARA
+fractions E-PARA
+. O
+
+
+Besides O
+, O
+plasticity S-PRO
+deterioration O
+of O
+the O
+repaired O
+tensile B-MACEQ
+specimens E-MACEQ
+is O
+mainly O
+attributed O
+to O
+the O
+formation O
+of O
+columnar B-CONPRI
+grain I-CONPRI
+boundary E-CONPRI
+α O
+phases O
+in O
+the O
+weld B-CONPRI
+zone E-CONPRI
+which O
+are O
+considered O
+to O
+be S-MATE
+the O
+earliest O
+nucleation S-CONPRI
+sites O
+of O
+microcracks S-CONPRI
+and O
+confirmed O
+by O
+in B-CONPRI
+situ E-CONPRI
+tensile O
+test O
+. O
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+
+With O
+the O
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+of O
+WZ S-CONPRI
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+in O
+the O
+cross B-CONPRI
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+tensile B-MACEQ
+specimens E-MACEQ
+, O
+the O
+plasticity S-PRO
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+the O
+alloy S-MATE
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+decreases O
+. O
+
+
+Ultrasonic B-MANP
+additive I-MANP
+manufacturing E-MANP
+( O
+UAM S-MANP
+) O
+is O
+a O
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+with O
+mechanized O
+tape O
+layering O
+to O
+fabricate S-MANP
+fully O
+functional O
+parts O
+. O
+
+
+However O
+, O
+parts O
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+a O
+reduction S-CONPRI
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+normal O
+to O
+the O
+welding B-FEAT
+interfaces E-FEAT
+( O
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+) O
+. O
+
+
+In O
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+work O
+, O
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+( O
+PWHT S-CONPRI
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+Al-6061 S-MATE
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+aiming O
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+improve O
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+the O
+UAM S-MANP
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+
+
+Tensile B-CHAR
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+( O
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+coupled O
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+metallography S-CONPRI
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+rationalize O
+the O
+mechanical S-APPL
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+of O
+the O
+UAM S-MANP
+builds S-CHAR
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+
+
+It O
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+factor O
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+~3÷3.5 O
+( O
+from O
+~46 O
+to O
+177 O
+MPa S-CONPRI
+) O
+. O
+
+
+The O
+improvements O
+in O
+the O
+strength S-PRO
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+material B-CONPRI
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+grain B-CONPRI
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+
+
+Ultrasonic B-MANP
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+fundamental O
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+fabricate S-MANP
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+( O
+3-D S-CONPRI
+) O
+components S-MACEQ
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+
+
+One O
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+this O
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+poor O
+tensile B-PRO
+strength E-PRO
+along O
+the O
+z-axis S-CONPRI
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+
+
+Recent O
+work O
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+demonstrated O
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+of O
+the O
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+post-processing B-MANP
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+
+
+The O
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+high O
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+the O
+interface S-CONPRI
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+treatments E-MANP
+is O
+, O
+however O
+, O
+not O
+yet O
+well O
+understood O
+. O
+
+
+In O
+this O
+work O
+we O
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+multiscale O
+characterization O
+to O
+understand O
+the O
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+of O
+the O
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+post-weld B-MANP
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+treatments E-MANP
+. O
+
+
+Aluminum B-MATE
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+6061 O
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+fabricated S-CONPRI
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+post-weld B-MANP
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+at O
+180 O
+, O
+330 O
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+580 O
+°C O
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+
+The O
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+to O
+the O
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+interfaces O
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+, O
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+
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+takes O
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+
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+
+Based O
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+
+
+Additive B-MANP
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+
+The O
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+
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+
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+
+Once O
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+, O
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+make O
+the O
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+. O
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+
+Previous O
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+such O
+as S-MATE
+prismatic O
+and O
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+
+Efficient O
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+weld-deposition S-CONPRI
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+
+Uses O
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+
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+
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+
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+
+Due O
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+
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+
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+
+This O
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+
+An O
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+A O
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+Some O
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+
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+processing O
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+
+
+With O
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+
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+
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+
+The O
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+
+The O
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+variation S-CONPRI
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+different O
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+
+The O
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+
+The O
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+detail O
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+the O
+weld B-CONPRI
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+
+This O
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+AA6061 S-MATE
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+
+It O
+describes O
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+multi-layered O
+similar O
+and O
+dissimilar O
+metallic B-MATE
+sheets E-MATE
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+
+
+The O
+method O
+described O
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+rod S-MACEQ
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+AISI B-MATE
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+pressure S-CONPRI
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+
+As S-MATE
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+distal O
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+upper O
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+axial B-CONPRI
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+applied O
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+
+After O
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+
+Multi-track O
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+, O
+C-Mn B-MATE
+steel E-MATE
+, O
+Nickel-based B-MATE
+alloys E-MATE
+, O
+Cp O
+Cu S-MATE
+, O
+Ti6Al4V S-MATE
+and O
+low O
+temperature S-PARA
+metallic B-MATE
+sheets E-MATE
+, O
+AA6061 S-MATE
+were O
+obtained O
+. O
+
+
+Optical S-CHAR
+and O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+examination O
+and O
+180 O
+degree O
+U-bend B-CHAR
+test E-CHAR
+indicated O
+that O
+defect S-CONPRI
+free O
+seam B-FEAT
+welds E-FEAT
+could O
+be S-MATE
+obtained O
+with O
+this O
+method O
+. O
+
+
+Tensile- B-CHAR
+shear I-CHAR
+testing E-CHAR
+showed O
+that O
+the O
+seam B-FEAT
+welds E-FEAT
+of O
+AISI B-MATE
+304 E-MATE
+, O
+C-Mn B-MATE
+steel E-MATE
+, O
+Nickel-based B-MATE
+alloy E-MATE
+were O
+stronger O
+than O
+the O
+starting O
+base B-MATE
+metal E-MATE
+counterparts O
+while O
+AA6061 S-MATE
+was O
+weaker O
+due O
+to O
+softening O
+. O
+
+
+The O
+metallurgical B-CONPRI
+bonding E-CONPRI
+at O
+the O
+interface S-CONPRI
+between O
+the O
+metallic B-MATE
+sheets E-MATE
+was O
+attributed O
+to O
+localized O
+stick O
+and O
+slip O
+at O
+the O
+interface S-CONPRI
+, O
+dynamic S-CONPRI
+recrystallization O
+and O
+diffusion S-CONPRI
+. O
+
+
+The O
+method O
+developed O
+can O
+be S-MATE
+used O
+as S-MATE
+a O
+means O
+of O
+welding S-MANP
+, O
+cladding S-MANP
+and O
+additive B-MANP
+manufacturing E-MANP
+. O
+
+
+In O
+this O
+paper O
+the O
+joinability O
+of O
+titanium S-MATE
+Additive B-MANP
+Manufactured E-MANP
+( O
+AM S-MANP
+) O
+parts O
+is O
+explored O
+. O
+
+
+Keyhole B-MANP
+welding E-MANP
+, O
+using O
+a O
+pulsed B-ENAT
+laser I-ENAT
+beam E-ENAT
+, O
+of O
+conventionally O
+produced O
+parts O
+is O
+compared O
+to O
+AM B-MACEQ
+parts E-MACEQ
+. O
+
+
+Metal B-MANP
+AM E-MANP
+parts O
+are O
+notorious O
+for O
+having O
+remaining O
+porosities S-PRO
+and O
+other O
+non-isotropic S-CONPRI
+properties O
+due O
+to O
+the O
+layered O
+manufacturing B-MANP
+process E-MANP
+. O
+
+
+This O
+study O
+shows O
+that O
+due O
+to O
+these O
+deficiencies O
+more O
+energy O
+per O
+unit O
+weld B-PARA
+length E-PARA
+is O
+required O
+to O
+obtain O
+a O
+similar O
+keyhole O
+geometry S-CONPRI
+for O
+titanium S-MATE
+AM B-MACEQ
+parts E-MACEQ
+. O
+
+
+It O
+is O
+also O
+demonstrated O
+that O
+, O
+with O
+adjusted O
+laser S-ENAT
+process O
+parameters S-CONPRI
+, O
+good O
+quality B-CONPRI
+welds E-CONPRI
+for O
+aerospace S-APPL
+applications O
+in O
+terms O
+of O
+pressure B-PRO
+resistance E-PRO
+and O
+leak O
+tightness O
+are O
+achievable O
+. O
+
+
+Part O
+size O
+in O
+additive B-MANP
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+is O
+limited O
+by O
+the O
+size O
+of O
+building O
+area S-PARA
+of O
+AM S-MANP
+equipment O
+. O
+
+
+Occasionally O
+, O
+larger O
+constructions O
+that O
+AM B-MACEQ
+machines E-MACEQ
+are O
+able O
+to O
+produce O
+, O
+are O
+needed O
+, O
+and O
+this O
+creates O
+demand O
+for O
+welding S-MANP
+AM B-MACEQ
+parts E-MACEQ
+together O
+. O
+
+
+However O
+there O
+is O
+very O
+little O
+information O
+on O
+welding S-MANP
+of O
+additive B-MANP
+manufactured E-MANP
+stainless O
+steels S-MATE
+. O
+
+
+The O
+aim O
+of O
+this O
+study O
+was O
+to O
+investigate O
+the O
+weldability S-PRO
+aspects O
+of O
+AM B-MATE
+material E-MATE
+. O
+
+
+In O
+this O
+study O
+, O
+comparison O
+of O
+the O
+bead S-CHAR
+on O
+plate O
+welds S-FEAT
+between O
+AM B-MACEQ
+parts E-MACEQ
+and O
+sheet B-MATE
+metal E-MATE
+parts O
+is O
+done.Used O
+material S-MATE
+was O
+316L B-MATE
+stainless I-MATE
+steel E-MATE
+, O
+AM S-MANP
+and O
+sheet B-MATE
+metal E-MATE
+, O
+and O
+parts O
+were O
+welded S-MANP
+with O
+laser B-MANP
+welding E-MANP
+. O
+
+
+Weld B-PARA
+quality E-PARA
+was O
+evaluated O
+visually O
+from O
+macroscopic B-CONPRI
+images E-CONPRI
+. O
+
+
+Results O
+show O
+that O
+there O
+are O
+certain O
+differences O
+in O
+the O
+welds S-FEAT
+in O
+AM B-MACEQ
+parts E-MACEQ
+compared O
+to O
+the O
+welds S-FEAT
+in O
+sheet B-MATE
+metal E-MATE
+parts O
+. O
+
+
+Differences O
+were O
+found O
+in O
+penetration B-PARA
+depths E-PARA
+and O
+in O
+type O
+of O
+welding B-CONPRI
+defects E-CONPRI
+. O
+
+
+Nevertheless O
+, O
+this O
+study O
+presents O
+that O
+laser B-MANP
+welding E-MANP
+is O
+suitable O
+process S-CONPRI
+for O
+welding S-MANP
+AM B-MACEQ
+parts E-MACEQ
+. O
+
+
+Additive B-MANP
+manufacturing E-MANP
+( O
+AM S-MANP
+) O
+of O
+high O
+γ′ O
+strengthened O
+Nickel-base B-MATE
+superalloys E-MATE
+, O
+such O
+as S-MATE
+IN738LC O
+, O
+is O
+of O
+high O
+interest O
+for O
+applications O
+in O
+hot O
+section O
+components S-MACEQ
+for O
+gas B-MACEQ
+turbines E-MACEQ
+. O
+
+
+The O
+creep S-PRO
+property O
+acts O
+as S-MATE
+the O
+critical O
+indicator O
+of O
+component S-MACEQ
+performance O
+under O
+load O
+at O
+elevated O
+temperature S-PARA
+. O
+
+
+In O
+order O
+to O
+evaluate O
+the O
+short-term O
+creep B-PRO
+behavior E-PRO
+, O
+slow B-CONPRI
+strain I-CONPRI
+rate I-CONPRI
+tensile E-CONPRI
+( O
+SSRT S-CONPRI
+) O
+tests O
+were O
+performed O
+. O
+
+
+IN738LC S-MATE
+bars O
+were O
+built O
+by O
+laser B-MANP
+powder-bed-fusion E-MANP
+( O
+L-PBF S-MANP
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+and O
+then O
+subjected O
+to O
+hot B-MANP
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+( O
+HIP S-MANP
+) O
+followed O
+by O
+the O
+standard S-CONPRI
+two-step O
+heat B-MANP
+treatment E-MANP
+. O
+
+
+The O
+samples S-CONPRI
+were O
+subjected O
+to O
+SSRT S-CONPRI
+testing O
+at O
+850 O
+°C O
+under O
+strain B-CONPRI
+rates E-CONPRI
+of O
+1 O
+× O
+10−5/s O
+, O
+1 O
+× O
+10−6/s O
+, O
+and O
+1 O
+× O
+10−7/s O
+. O
+
+
+In O
+this O
+research S-CONPRI
+, O
+the O
+underlying O
+creep B-CONPRI
+deformation I-CONPRI
+mechanism E-CONPRI
+of O
+AM S-MANP
+processed O
+IN738LC S-MATE
+is O
+investigated O
+using O
+the O
+serial B-ENAT
+sectioning E-ENAT
+technique O
+, O
+electron B-CHAR
+backscatter I-CHAR
+diffraction E-CHAR
+( O
+EBSD S-CHAR
+) O
+, O
+transmission B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+TEM S-CHAR
+) O
+. O
+
+
+On O
+the O
+creep S-PRO
+mechanism O
+of O
+AM B-MATE
+polycrystalline I-MATE
+IN738LC E-MATE
+, O
+grain B-CONPRI
+boundary I-CONPRI
+sliding E-CONPRI
+is O
+predominant O
+. O
+
+
+However O
+, O
+due O
+to O
+the O
+interlock O
+feature S-FEAT
+of O
+grain B-CONPRI
+boundaries E-CONPRI
+in O
+AM S-MANP
+processed O
+IN738LC S-MATE
+, O
+the O
+grain B-CONPRI
+structure E-CONPRI
+retains O
+its O
+integrity S-CONPRI
+after O
+deformation S-CONPRI
+. O
+
+
+The O
+dislocation B-CONPRI
+motion E-CONPRI
+acts O
+as S-MATE
+the O
+major O
+accommodation O
+process S-CONPRI
+of O
+grain B-CONPRI
+boundary I-CONPRI
+sliding E-CONPRI
+. O
+
+
+Dislocations S-CONPRI
+bypass O
+the O
+γ′ O
+precipitates S-MATE
+by O
+Orowan B-CONPRI
+looping E-CONPRI
+and O
+wavy O
+slip O
+. O
+
+
+The O
+rearrangement O
+of O
+screw B-CONPRI
+dislocations E-CONPRI
+is O
+responsible O
+for O
+the O
+formation O
+of O
+subgrains S-CONPRI
+within O
+the O
+grain S-CONPRI
+interior O
+. O
+
+
+This O
+research S-CONPRI
+elucidates O
+the O
+short-creep S-CONPRI
+behavior O
+of O
+AM S-MANP
+processed O
+IN738LC S-MATE
+. O
+
+
+It O
+also O
+shed O
+new O
+light O
+on O
+the O
+creep B-CONPRI
+deformation I-CONPRI
+mechanism E-CONPRI
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+additive B-MANP
+manufactured E-MANP
+γ′ O
+strengthened O
+polycrystalline O
+Nickel-base B-MATE
+superalloys E-MATE
+. O
+
+
+Due O
+to O
+the O
+cost O
+advantage O
+, O
+weld-based B-MANP
+Additive I-MANP
+Manufacturing E-MANP
+( O
+AM S-MANP
+) O
+is O
+suitable O
+for O
+directly O
+fabricating S-MANP
+large O
+metallic B-MACEQ
+parts E-MACEQ
+. O
+
+
+One O
+of O
+challenges O
+for O
+weld-based O
+Additive S-MATE
+M O
+anufacturing O
+is O
+to O
+build S-PARA
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+structure S-CONPRI
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+tilt B-FEAT
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+at O
+a O
+large O
+slant B-PARA
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+the O
+boundary S-FEAT
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+flow O
+down O
+by O
+gravity O
+due O
+to O
+lack O
+of O
+sufficient O
+support S-APPL
+. O
+
+
+In O
+the O
+present O
+work O
+, O
+electromagnetically S-CONPRI
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+weld-based B-MANP
+Additive I-MANP
+Manufacturing E-MANP
+is O
+develop O
+ed S-CHAR
+to O
+solve O
+this O
+problem O
+. O
+
+
+In O
+the O
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+, O
+liquid B-MATE
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+confined O
+and O
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+liquid B-MATE
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+restricted O
+. O
+
+
+Experiments O
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+numerical B-ENAT
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+performed O
+to O
+investigate O
+the O
+effect O
+mechanism S-CONPRI
+of O
+electromagnetic B-CONPRI
+confinement E-CONPRI
+. O
+
+
+Experimental S-CONPRI
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+verify O
+that O
+the O
+flow-down O
+or O
+collapse O
+of O
+liquid B-MATE
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+
+With O
+specific O
+welding S-MANP
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+maximum O
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+successful O
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+50° O
+to O
+60° O
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+imposing O
+electromagnetic B-CONPRI
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+
+
+New O
+technologies S-CONPRI
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+the O
+advent O
+of O
+the O
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+various O
+geometries S-CONPRI
+, O
+good O
+accuracy S-CHAR
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+material S-MATE
+waste O
+reduction S-CONPRI
+savings O
+. O
+
+
+This O
+circumstance O
+requires O
+the O
+application O
+of O
+techniques O
+to O
+determine O
+the O
+reliability S-CHAR
+of O
+the O
+results O
+in O
+the O
+deposition S-CONPRI
+of O
+layers O
+in O
+order O
+to O
+have O
+a O
+good O
+accuracy S-CHAR
+. O
+
+
+This O
+work O
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+to O
+present O
+a O
+new O
+technology S-CONPRI
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+to O
+additive B-MANP
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+focusing O
+on O
+accuracy S-CHAR
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+the O
+deposition S-CONPRI
+of O
+layers O
+, O
+lower O
+cost O
+and O
+user O
+friendliness O
+man-machine O
+. O
+
+
+New O
+method O
+was O
+proposed O
+in O
+order O
+to O
+obtain O
+advantages O
+regarding O
+the O
+use O
+of O
+Plasma B-MANP
+welding E-MANP
+process O
+. O
+
+
+An O
+apparatus O
+for O
+generating O
+plasma S-CONPRI
+was O
+used O
+to O
+obtain O
+the O
+arc S-CONPRI
+. O
+
+
+Correlated S-CONPRI
+magnitudes O
+helped O
+in O
+determining O
+Efficient O
+Model S-CONPRI
+of O
+Deposition S-CONPRI
+for O
+use O
+in O
+offsetting O
+the O
+geometric O
+and O
+thermal O
+errors S-CONPRI
+. O
+
+
+Computer B-CONPRI
+simulations E-CONPRI
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+applied O
+to O
+the O
+new O
+concept O
+of O
+deposition S-CONPRI
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+the O
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+of O
+the O
+presented O
+system O
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+but O
+no O
+experimental S-CONPRI
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+are O
+provided O
+herein O
+. O
+
+
+Ultrasonic B-MANP
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+( O
+UAM S-MANP
+) O
+is O
+a O
+solid-state S-CONPRI
+hybrid B-CONPRI
+manufacturing E-CONPRI
+technique O
+. O
+
+
+In O
+this O
+work O
+characterization O
+using O
+electron B-ENAT
+back I-ENAT
+scatter I-ENAT
+diffraction E-ENAT
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+performed O
+on O
+aluminum–titanium O
+dissimilar O
+metal S-MATE
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+made O
+using O
+a O
+9 O
+kW O
+ultrasonic B-MANP
+additive I-MANP
+manufacturing E-MANP
+system O
+. O
+
+
+The O
+results O
+showed O
+that O
+the O
+aluminum S-MATE
+texture O
+at O
+the O
+interface S-CONPRI
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+ultrasonic B-MANP
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+is O
+similar O
+to O
+aluminum S-MATE
+texture O
+observed O
+during O
+accumulative O
+roll B-MANP
+bonding E-MANP
+of O
+aluminum B-MATE
+alloys E-MATE
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+
+
+It O
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+finally O
+concluded O
+that O
+the O
+underlying O
+mechanism S-CONPRI
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+bond O
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+relies O
+on O
+severe O
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+the O
+interface S-CONPRI
+. O
+
+
+The O
+wire B-MANP
+arc I-MANP
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+WAAM S-MANP
+) O
+2Cr13 O
+thin-wall O
+part O
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+using O
+robotic O
+cold B-MANP
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+( O
+CMT S-MANP
+) O
+technology S-CONPRI
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+and O
+the O
+location-related O
+thermal O
+history O
+, O
+densification S-MANP
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+, O
+microstructure S-CONPRI
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+and O
+mechanical B-CONPRI
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+the O
+part O
+were O
+explored O
+. O
+
+
+The O
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+pre-heating O
+effect O
+from O
+previously O
+built O
+layers O
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+to O
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+rapidly O
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+then O
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+stable O
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+the O
+15th–25th O
+layers O
+. O
+
+
+The O
+peaks O
+of O
+the O
+α-Fe O
+phase S-CONPRI
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+the O
+AM B-MACEQ
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+a O
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+'s O
+angle O
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+result O
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+solute B-MATE
+atoms E-MATE
+incorporation O
+when O
+compared O
+with O
+that O
+of O
+the O
+base B-MATE
+metal E-MATE
+. O
+
+
+As-deposited O
+microstructure S-CONPRI
+consisted O
+of O
+martensite S-MATE
+and O
+ferrite S-MATE
+, O
+along O
+with O
+( O
+Fe S-MATE
+, O
+Cr S-MATE
+) O
+23C6 O
+phase S-CONPRI
+precipitated O
+at O
+α-Fe O
+grain B-CONPRI
+boundaries E-CONPRI
+. O
+
+
+Martensite S-MATE
+content O
+increased O
+gradually O
+from O
+the O
+5th O
+layer S-PARA
+to O
+the O
+25th O
+layers O
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+
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+20th O
+layer S-PARA
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+
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+
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+
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+
+This O
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+
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+
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+
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+
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+
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+
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+
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+
+Amorphous O
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+filament-by-filament O
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+
+Non-isothermal O
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+
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+
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+
+The O
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+
+However O
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+
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+In O
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+
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+
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+
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+
+Void S-CONPRI
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+
+The O
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+
+A O
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+
+Robotic O
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+
+It O
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+
+Ideally O
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+
+Thus O
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+This O
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+
+Firstly O
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+
+Subsequently O
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+distance O
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+, O
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+positional O
+deposition S-CONPRI
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+
+Finally O
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+remarkable O
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+past O
+decade O
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+
+In O
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+effect O
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+welding S-MANP
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+additively O
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+
+MIG B-MANP
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+chosen O
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+present O
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+spool S-MACEQ
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+
+This O
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+Taguchi B-CONPRI
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+
+Waviness S-FEAT
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+
+L9 O
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+
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+A O
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+
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+0.55 O
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+3.07 O
+mm S-MANP
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+
+0.25 O
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+28 O
+V S-MATE
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+15.83 O
+mm S-MANP
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+
+
+Confirmation O
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+obtained O
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+
+Even O
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+
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+
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+
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+Embedding O
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+
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+
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+inserted O
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+
+To O
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+
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+the O
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+interior O
+. O
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+
+In O
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+a O
+single O
+weld B-CONPRI
+bead E-CONPRI
+resembles O
+a O
+parabola O
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+
+In O
+order O
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+the O
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+be S-MATE
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+
+
+This O
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+novel O
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+. O
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+
+Mathematical S-CONPRI
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+weld B-CONPRI
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+accounting O
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+overlapping O
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+
+The O
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+
+
+Macrographs O
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+to O
+analyze O
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+boundary S-FEAT
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+. O
+
+
+High-integrity O
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+, O
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+
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+
+In O
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+. O
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+
+UAM S-MANP
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+
+The O
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+( O
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+
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+
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+
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+Polypropylene S-MATE
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
+In O
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+
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+The O
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+The O
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+The O
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+section O
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+
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+tenons O
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+( O
+or O
+sheets S-MATE
+) O
+. O
+
+
+The O
+workability O
+limits S-CONPRI
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+of O
+an O
+analytical O
+model S-CONPRI
+that O
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+, O
+instability O
+and O
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+
+
+Experimental S-CONPRI
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+develop O
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+
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+
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+
+AM S-MANP
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+
+The O
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+
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+
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+
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+
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+
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+superalloys S-MATE
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+
+Additive B-MANP
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+
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+
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+
+There O
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+
+In O
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+
+The O
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+
+To O
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+two O
+hatch O
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+
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+
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+
+The O
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+the O
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+
+Since O
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+achieve O
+part O
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+
+An O
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+For O
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+influenced O
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+
+The O
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+
+Additive B-MANP
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+
+While O
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+
+The O
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+
+In O
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+
+Tests O
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+
+In O
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+aluminium B-MATE
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+
+The O
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+branch O
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+developed O
+for O
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+
+
+However O
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+that O
+of O
+other O
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+
+Plastic S-MATE
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+
+To O
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+each O
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+
+Key O
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+each O
+cycle O
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+
+Qualitative S-CONPRI
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+the O
+mechanism S-CONPRI
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+flow O
+. O
+
+
+Analysis O
+of O
+driving O
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+
+Quantitative S-CONPRI
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+
+3D S-CONPRI
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+of O
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+
+
+Semi-qualitatively O
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+
+A O
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+
+Numerical B-ENAT
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+both O
+used O
+to O
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+flow O
+, O
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+solidification S-CONPRI
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+
+
+The O
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+driving O
+force S-CONPRI
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+quantitatively S-CONPRI
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+
+Numerical O
+method O
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+also O
+carried O
+out O
+to O
+understand O
+the O
+importance O
+of O
+different O
+driving O
+forces S-CONPRI
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+respectively O
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+
+The O
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+sequentially O
+coupled O
+to O
+the O
+thermal-fluid O
+model S-CONPRI
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+calculate O
+four O
+solidification B-CONPRI
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+
+Temperature B-PARA
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+observed O
+to O
+be S-MATE
+much O
+larger O
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+front O
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+the O
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+
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+
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+
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+
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+
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+
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+
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+
+The O
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+Module O
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+
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+
+The O
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+
+For O
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+
+It O
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+the O
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+by O
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+welding S-MANP
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+
+In O
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+different O
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+
+A O
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+
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+
+This O
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+
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+
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+
+It O
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+losses O
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+
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+
+To O
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+
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+
+We O
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+
+The O
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+way O
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+
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+
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+the O
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+
+In O
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+the O
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+
+The O
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+also O
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+
+This O
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+The O
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+
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+
+Here O
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+
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+
+Furthermore O
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+
+The O
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+
+This O
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+advanced O
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+
+Due O
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+This O
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+
+The O
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+
+The O
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+crucial O
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+the O
+future O
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+
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+FGMs O
+) O
+to O
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+
+The O
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+prove O
+the O
+efficacy O
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+the O
+NDT S-CONPRI
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+real O
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+
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+additive B-MANP
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+is O
+an O
+emerging O
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+
+Multiple O
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+be S-MATE
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+to O
+produce O
+multi-material S-CONPRI
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+objects O
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+
+
+Robotic-systems O
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+
+The O
+additive B-MANP
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+the O
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+tremendously O
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+
+This O
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+
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+
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+
+Examples O
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+the O
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+robotic-assisted O
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+
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+weld S-FEAT
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+
+In O
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+pressuriser O
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+
+
+Attention O
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+
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+
+The O
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+by O
+welding S-MANP
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+exceeds O
+60 O
+years O
+. O
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+
+With O
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+
+130 O
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+
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+GTA O
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+
+Deposition S-CONPRI
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+controlled O
+with O
+a O
+feedback S-PARA
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+
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+. O
+
+
+Additive B-MANP
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+Gas S-CONPRI
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+fabricating S-MANP
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+dense O
+metal S-MATE
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+
+In O
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+work O
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+a O
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+comprising O
+a O
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+
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+next O
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+
+The O
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+
+The O
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+
+Titanium S-MATE
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+orthopedics O
+, O
+dentistry S-APPL
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+
+There O
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+wearing O
+, O
+osteoporosis O
+etc O
+. O
+
+
+The O
+Cp- O
+Titanium S-MATE
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+titanium-based O
+alloys S-MATE
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+ways O
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++ O
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+comparative O
+analysis O
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+
+This O
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+. O
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+
+Two O
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+Mn S-MATE
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+
+To O
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+1100 O
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+
+Microstructure S-CONPRI
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+
+Work B-MANP
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+
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+
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+
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+
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+
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+
+In O
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+
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+
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+
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+
+Barriers O
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+A O
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+a O
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+
+A O
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+
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+
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+
+Currently O
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+
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+
+The O
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+
+Wire B-MANP
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+WAAM S-MANP
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+
+The O
+basis O
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+the O
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+. O
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+
+The O
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+geometric O
+area S-PARA
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+adjacent O
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+ignore O
+the O
+spreading O
+of O
+the O
+melted S-CONPRI
+weld O
+beads S-CHAR
+. O
+
+
+The O
+objective O
+of O
+the O
+research S-CONPRI
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+to O
+develop O
+an O
+enhanced O
+BOM O
+( O
+E.BOM O
+) O
+for O
+WAAM S-MANP
+, O
+which O
+takes O
+the O
+spreading O
+of O
+the O
+weld B-CONPRI
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+into O
+consideration O
+. O
+
+
+A O
+deposited B-CHAR
+bead E-CHAR
+spreads O
+to O
+the O
+already O
+deposited O
+neighboring O
+bead S-CHAR
+and O
+as S-MATE
+a O
+consequence O
+, O
+its O
+center O
+point O
+deviates O
+from O
+the O
+center O
+point O
+of O
+the O
+fed O
+( O
+to O
+be S-MATE
+melted O
+) O
+wire O
+. O
+
+
+Experiments O
+were O
+designed S-FEAT
+to O
+explore O
+the O
+relationships O
+between O
+the O
+geometries S-CONPRI
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+the O
+beads S-CHAR
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+and O
+the O
+offset S-CONPRI
+distance O
+between O
+the O
+center O
+of O
+a O
+weld B-CONPRI
+bead E-CONPRI
+and O
+the O
+center O
+of O
+the O
+fed O
+wire O
+. O
+
+
+An O
+artificial B-ENAT
+neural I-ENAT
+network E-ENAT
+was O
+used O
+to O
+predict O
+the O
+offset S-CONPRI
+distance O
+of O
+a O
+certain O
+weld B-CONPRI
+bead E-CONPRI
+based O
+on O
+the O
+results O
+of O
+the O
+experiments O
+. O
+
+
+In O
+addition O
+, O
+a O
+reasoning O
+algorithm S-CONPRI
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+implemented O
+to O
+calculate O
+the O
+optimal O
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+the O
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+adjacent O
+deposition B-PARA
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+order O
+to O
+achieve O
+a O
+planned O
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+distance O
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+
+
+The O
+E.BOM O
+has O
+been O
+tested O
+by O
+validation S-CONPRI
+experiments O
+. O
+
+
+On O
+the O
+one O
+hand O
+, O
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+improves O
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+surface S-CONPRI
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+
+
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+manufacture S-CONPRI
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+tungsten S-MATE
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+micro-cracks S-CONPRI
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+the O
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+characteristic O
+low-temperature O
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+high O
+susceptibility S-PRO
+to O
+oxidation S-MANP
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+
+Powder B-MANP
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+is O
+typically O
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+manufacturing B-MANP
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+of O
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+
+Recently O
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+Additive I-MANP
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+capable O
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+produce O
+fully-dense O
+large-scale O
+metal S-MATE
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+relatively O
+low O
+cost O
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+using O
+high-quality O
+wire O
+as S-MATE
+feedstock O
+. O
+
+
+In O
+this O
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+, O
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+technique O
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+for O
+the O
+production S-MANP
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+large-scale O
+tungsten S-MATE
+linear O
+structures O
+. O
+
+
+The O
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+has O
+been O
+studied O
+and O
+optimised O
+to O
+obtain O
+defect-free O
+tungsten S-MATE
+deposits O
+. O
+
+
+In O
+particular O
+, O
+front O
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+eliminated O
+the O
+occurrence O
+of O
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+micro-cracks S-CONPRI
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+when O
+compared O
+to O
+side O
+wire B-PARA
+feeding E-PARA
+. O
+
+
+The O
+microstructure S-CONPRI
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+the O
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+their O
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+the O
+deposition B-MANP
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+discussed O
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+
+
+Despite O
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+
+This O
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+a O
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+large-scale O
+component S-MACEQ
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+the O
+dimension S-FEAT
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+210 O
+× O
+75 O
+× O
+12 O
+mm S-MANP
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+
+
+This O
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+a O
+potential O
+alternative O
+to O
+the O
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+route O
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+
+An O
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+
+With O
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+
+The O
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+
+The O
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+% O
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+fabricate S-MANP
+thin-wall O
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+a O
+proper O
+laser B-PARA
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+
+In O
+comparison O
+with O
+the O
+common O
+GMAW-based O
+AM S-MANP
+method O
+, O
+the O
+L-M O
+based O
+AM S-MANP
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+shows O
+feasibility S-CONPRI
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+narrower O
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+component S-MACEQ
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+better O
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+higher O
+stability S-PRO
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+also O
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+higher O
+deposition S-CONPRI
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+
+
+Wire B-MANP
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+Arc I-MANP
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+( O
+WAAM S-MANP
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+on O
+robotic B-MANP
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+
+This O
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+potential O
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+material S-MATE
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+due O
+to O
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+shape O
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+
+Empirical S-CONPRI
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+1 O
+kg/h O
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+site O
+of O
+MX3D O
+. O
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+
+The O
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+kg O
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+kW O
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+0.44 O
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+0.54 O
+by O
+the O
+ventilation O
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+
+
+The O
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+1.1 O
+% O
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+
+A O
+98 O
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+( O
+LCA O
+) O
+was O
+performed O
+. O
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+
+To O
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+this O
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+, O
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+literature O
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+
+
+The O
+purpose O
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+develop O
+insight O
+into O
+the O
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+WAAM S-MANP
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+
+
+Results O
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+
+It O
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+0.75 O
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+
+
+Stainless B-MATE
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+
+When O
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+for O
+each O
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+
+
+Results O
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+significantly O
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+on O
+product O
+shape O
+, O
+function O
+, O
+materials S-CONPRI
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+
+Method O
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+
+Method O
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+metal S-MATE
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+
+Effect O
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+
+
+Stress B-CHAR
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+a O
+significant O
+influence O
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+of O
+welded B-FEAT
+joints E-FEAT
+. O
+
+
+In O
+order O
+to O
+reduce O
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+welded B-FEAT
+joints E-FEAT
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+mathematical S-CONPRI
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+( O
+MTT O
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+on O
+bionics O
+was O
+applied O
+to O
+weld S-FEAT
+shape O
+design S-FEAT
+. O
+
+
+Accordingly O
+, O
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+stress B-CHAR
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+various O
+weld B-CONPRI
+beads E-CONPRI
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+the O
+corner O
+boxing O
+welded B-FEAT
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+the O
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+T-joint S-FEAT
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+dissected O
+using O
+our O
+in-house O
+FEM S-CONPRI
+software O
+JWRIAN O
+. O
+
+
+It O
+was O
+found O
+that O
+there O
+existed O
+a O
+large O
+stress B-CHAR
+concentration E-CHAR
+in O
+the O
+conventional O
+welded B-FEAT
+joints E-FEAT
+, O
+whereas O
+those O
+welded B-FEAT
+joints E-FEAT
+with O
+elongated O
+weld B-CONPRI
+bead E-CONPRI
+were O
+accompanied O
+by O
+a O
+lower O
+stress B-CHAR
+concentration E-CHAR
+, O
+especially O
+for O
+elongated O
+weld B-CONPRI
+bead E-CONPRI
+with O
+MTT O
+design S-FEAT
+. O
+
+
+Furthermore O
+, O
+among O
+the O
+weld S-FEAT
+shapes O
+of O
+the O
+corner O
+boxing O
+fillet S-FEAT
+welded O
+joint S-CONPRI
+, O
+the O
+rectangle O
+shape O
+of O
+weld B-CONPRI
+bead E-CONPRI
+had O
+the O
+minimum O
+stress B-CHAR
+concentration E-CHAR
+factor O
+( O
+1.05 O
+) O
+. O
+
+
+For O
+the O
+fillet S-FEAT
+welded O
+T-joint S-FEAT
+with O
+MTT O
+design S-FEAT
+, O
+the O
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+decreased O
+dramatically O
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+the O
+increase O
+of O
+the O
+index O
+of O
+designed S-FEAT
+shape O
+, O
+but O
+there O
+was O
+a O
+minor O
+difference O
+of O
+stress B-CHAR
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+at O
+weld S-FEAT
+root O
+between O
+the O
+weld B-CONPRI
+beads E-CONPRI
+with O
+MTT O
+design S-FEAT
+. O
+
+
+In O
+addition O
+, O
+application O
+of O
+low O
+transformation O
+temperature S-PARA
+( O
+LTT O
+) O
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+utilizing O
+martensitic O
+transformation O
+to O
+the O
+fillet S-FEAT
+welded O
+T-joints O
+can O
+produce O
+compressive O
+residual B-PRO
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+at O
+weld S-FEAT
+toe O
+. O
+
+
+Additive-manufactured O
+AlSi10Mg S-MATE
+boxes O
+were O
+studied O
+under O
+lateral O
+crushing S-CONPRI
+. O
+
+
+Experimental S-CONPRI
+tests O
+and O
+numerical B-ENAT
+simulations E-ENAT
+were O
+conducted O
+. O
+
+
+The O
+constitutive O
+model S-CONPRI
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+calibrated S-CONPRI
+using O
+tensile B-CHAR
+tests E-CHAR
+in O
+three O
+directions O
+. O
+
+
+The O
+influence O
+of O
+the O
+yield O
+surface S-CONPRI
+, O
+the O
+adopted O
+thickness O
+and O
+the O
+element S-MATE
+type O
+were O
+studied O
+. O
+
+
+An O
+experimental S-CONPRI
+and O
+numerical O
+study O
+on O
+the O
+quasi-static S-CONPRI
+loading O
+of O
+AlSi10Mg S-MATE
+square O
+boxes O
+produced O
+by O
+selective B-MANP
+laser I-MANP
+melting E-MANP
+( O
+SLM S-MANP
+) O
+was O
+carried O
+out O
+. O
+
+
+The O
+goal O
+was O
+to O
+evaluate O
+the O
+applicability O
+of O
+common O
+finite B-CHAR
+element I-CHAR
+modelling E-CHAR
+techniques O
+to O
+3D-printed B-APPL
+parts E-APPL
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+material S-MATE
+and O
+component S-MACEQ
+scales O
+, O
+under O
+large O
+deformations S-CONPRI
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+fracture S-CONPRI
+. O
+
+
+Uniaxial O
+tensile B-MACEQ
+specimens E-MACEQ
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+
+Modeling S-ENAT
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+prediction S-CONPRI
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+( O
+FSW S-MANP
+) O
+process S-CONPRI
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+an O
+important O
+role O
+that O
+has O
+not O
+been O
+elaborated O
+in O
+the O
+literature O
+. O
+
+
+That O
+model S-CONPRI
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+suitable O
+for O
+the O
+pure O
+( O
+intrinsic O
+) O
+diffusion S-CONPRI
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+not O
+consider O
+the O
+main O
+unique O
+characteristic O
+of O
+FSW S-MANP
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+, O
+the O
+stirring O
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+an O
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+) O
+. O
+
+
+To O
+address O
+this O
+research S-CONPRI
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+, O
+first O
+, O
+we O
+develop O
+a O
+new O
+model S-CONPRI
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+the O
+IMC O
+thickness O
+that O
+takes O
+the O
+velocity O
+of O
+particles S-CONPRI
+into O
+account O
+. O
+
+
+Second O
+, O
+we O
+provide O
+an O
+analysis O
+on O
+the O
+velocity O
+of O
+particles S-CONPRI
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+FSW S-MANP
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+on O
+vortex O
+dynamics O
+. O
+
+
+Third O
+, O
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+analyze O
+the O
+proposed O
+IMC O
+thickness O
+model S-CONPRI
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+experimental B-CONPRI
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+, O
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+our O
+model S-CONPRI
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+and O
+finally O
+examine O
+a O
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+
+
+Understanding O
+various O
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+further O
+lead S-MATE
+to O
+the O
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+of O
+the O
+existing O
+processes S-CONPRI
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+the O
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+of O
+novel O
+processes S-CONPRI
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+
+
+Inconel B-MATE
+718 E-MATE
+thin O
+wall O
+was O
+fabricated S-CONPRI
+by O
+PPAAM O
+. O
+
+
+Both O
+CET O
+and O
+DCT O
+can O
+be S-MATE
+found O
+in O
+the O
+as-built O
+sample S-CONPRI
+. O
+
+
+Temperature B-PARA
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+SDA O
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+contribute O
+to O
+grain B-CONPRI
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+
+
+The O
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+sensitive O
+to O
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+
+Abundant O
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+phases O
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+mechanical B-CONPRI
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+
+
+Inconel B-MATE
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+wall O
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+( O
+PPAAM O
+) O
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+is O
+more O
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+and O
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+in O
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+with O
+other O
+high O
+energy O
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+technologies O
+. O
+
+
+During O
+PPAAM O
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+layer B-CONPRI
+by I-CONPRI
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+decrease O
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+heat B-PRO
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+
+
+The O
+as-fabricated O
+sample S-CONPRI
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+diverse O
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+at O
+different O
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+. O
+
+
+Columnar B-MATE
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+, O
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+
+The O
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+
+After O
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+number O
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+and O
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+phases O
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+
+Besides O
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+phases O
+could O
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+be S-MATE
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+
+
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+precipitation S-CONPRI
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+
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+
+
+Applying O
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+the O
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+comparable O
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+to O
+the O
+precipitation S-CONPRI
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+phases E-CONPRI
+. O
+
+
+Maraging B-MATE
+steel E-MATE
+microlattice O
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+printed O
+by O
+SLM S-MANP
+, O
+crushed O
+, O
+and O
+simulated O
+using O
+FEM S-CONPRI
+. O
+
+
+SEM S-CHAR
+and O
+micro-CT S-CHAR
+was O
+performed O
+on O
+as-built O
+samples S-CONPRI
+to O
+verify O
+structural B-PRO
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+
+
+Two O
+modeling S-ENAT
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+are O
+presented O
+based O
+on O
+as-built O
+and O
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+geometries S-CONPRI
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+
+
+FESEM S-CHAR
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+performed O
+on O
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+failure S-CONPRI
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+
+Good O
+agreement O
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+found O
+between O
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+experiment S-CONPRI
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+the O
+simulations S-ENAT
+. O
+
+
+Additive S-MATE
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+manufacturing S-MANP
+techniques O
+, O
+in O
+particular O
+laser-based O
+powder B-MANP
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+methods O
+, O
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+revolutionary O
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+their O
+capabilities O
+to O
+fabricating S-MANP
+new O
+classes O
+of O
+lightweight S-CONPRI
+and O
+complex O
+materials S-CONPRI
+called O
+metallic S-MATE
+microlattices O
+. O
+
+
+In O
+this O
+paper O
+, O
+a O
+microlattice O
+structure S-CONPRI
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+designed S-FEAT
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+energy B-CHAR
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+further O
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+
+In O
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+. O
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+
+The O
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+
+In O
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+
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+
+The O
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+
+Finally O
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+
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+
+In O
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+
+In O
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+
+Furthermore O
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+The O
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+
+Microscope S-MACEQ
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+interfaces O
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+bonding S-CONPRI
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+
+Still O
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+Ferritic/martensitic O
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+
+
+FM O
+steels S-MATE
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+reactor O
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+, O
+casting S-MANP
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+, O
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+of O
+interest O
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+
+Here O
+, O
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+laser-blown-powder O
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+
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+
+The O
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+
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+
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+
+The O
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+
+The O
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+almost O
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+, O
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+the O
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+metallic B-MATE
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+original O
+material S-MATE
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+
+
+Additive B-MANP
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+bulk O
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+
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+
+They O
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+. O
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+
+Conversely O
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+
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+
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+
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+
+The O
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+understanding O
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+the O
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+presence O
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+partial B-CONPRI
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+the O
+process S-CONPRI
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+
+Few O
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+been O
+conducted O
+to O
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+M5 O
+’ O
+regression S-CONPRI
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+
+MGGP S-ENAT
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+the O
+most O
+popular O
+variant O
+of O
+GP S-CONPRI
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+recently O
+. O
+
+
+Those O
+approaches O
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+a O
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+a O
+mathematical B-CONPRI
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+mechanical B-CONPRI
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+given O
+input O
+parameters S-CONPRI
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+
+The O
+performance S-CONPRI
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+ANN S-ENAT
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+to O
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+than O
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+the O
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+of O
+ANN S-ENAT
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+predicting O
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+performance S-CONPRI
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+prototype S-CONPRI
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+
+The O
+STL S-MANS
+( O
+STereoLithography S-MANP
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+Standard B-MANS
+Tessellation I-MANS
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+a O
+standard S-CONPRI
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+additive B-MANP
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+. O
+
+
+The O
+STL S-MANS
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+process S-CONPRI
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+the O
+continuous O
+geometry S-CONPRI
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+the O
+CAD B-MANS
+file E-MANS
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+header S-CONPRI
+, O
+small O
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+, O
+y S-MATE
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+z O
+coordinates S-PARA
+and O
+the O
+normal B-CONPRI
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+to O
+the O
+triangles O
+. O
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+
+Each O
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+identified O
+by O
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+normal B-CONPRI
+vector E-CONPRI
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+vertices S-PARA
+. O
+
+
+The O
+facets S-CONPRI
+define O
+the O
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+a O
+3D B-APPL
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+
+Each O
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+part O
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+the O
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+the O
+interior O
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+exterior O
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+
+
+The O
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+STL S-MANS
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+
+The O
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+the O
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+stair I-CONPRI
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+
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+the O
+slicing B-CONPRI
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+
+
+Today O
+, O
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+computation S-CONPRI
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+the O
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+generation E-CONPRI
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+process B-CONPRI
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+
+The O
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+refined O
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+
+More O
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+
+According O
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+than O
+$ O
+5000 O
+. O
+
+
+The O
+Cornell O
+University O
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+Bath O
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+the O
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+@ O
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+
+The O
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+
+It O
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+typically O
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+
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+
+A O
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+$ O
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+
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+
+The O
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+
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+
+Both O
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+
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+dentistry S-APPL
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+, O
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+market O
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+Aerospace S-APPL
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+the O
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+
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+
+combine O
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+
+Thus O
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+we O
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+
+Authors O
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+Chuck S-MACEQ
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+
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+using O
+light O
+to O
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+solidify S-CONPRI
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+
+The O
+laser B-MANP
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+is O
+currently O
+one O
+of O
+the O
+most O
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+
+Models O
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+scanning S-CONPRI
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+a O
+photopolymer S-MATE
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+. O
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+
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+
+
+Ceramic B-MATE
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+
+The O
+building B-CHAR
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+same O
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+a O
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+
+The O
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+
+A O
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+less O
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+10 O
+μm O
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+
+The O
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+the O
+same O
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+its O
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+in O
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+
+In O
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+
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+
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+the O
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+by O
+a O
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+
+A O
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+points O
+defined O
+by O
+the O
+computer-generated S-CONPRI
+component S-MACEQ
+design O
+data S-CONPRI
+. O
+
+
+The O
+platform S-MACEQ
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+then O
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+and O
+another O
+layer S-PARA
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+powder S-MATE
+is O
+applied O
+. O
+
+
+Once O
+again O
+the O
+material S-MATE
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+fused S-CONPRI
+so O
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+to O
+bond O
+with O
+the O
+layer S-PARA
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+at O
+the O
+predefined B-CONPRI
+points E-CONPRI
+. O
+
+
+During O
+the O
+process S-CONPRI
+, O
+successive O
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+metal B-MATE
+powder E-MATE
+are O
+fully O
+melted S-CONPRI
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+consolidated O
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+top O
+of O
+each O
+other O
+. O
+
+
+Today O
+, O
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+3D B-MACEQ
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+. O
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+
+The O
+material S-MATE
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+steel S-MATE
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+steel E-MATE
+, O
+cobalt B-MATE
+chrome E-MATE
+, O
+titanium S-MATE
+and O
+aluminium S-MATE
+. O
+
+
+Electron B-MANP
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+Melting E-MANP
+is O
+a O
+powder B-MANP
+process E-MANP
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+by O
+its O
+superior O
+accuracy S-CHAR
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+high-power O
+electron B-CONPRI
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+( O
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+3000 O
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+that O
+generates O
+the O
+energy O
+needed O
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+high O
+melting B-CONPRI
+capacity E-CONPRI
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+high O
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+
+Selective B-MANP
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+( O
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+fuse S-MANP
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+, O
+titanium S-MATE
+, O
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+, O
+ceramic B-MATE
+powders E-MATE
+, O
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+) O
+. O
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+
+As S-MATE
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+lowered O
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+the O
+process S-CONPRI
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+repeated O
+until O
+the O
+model S-CONPRI
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+. O
+
+
+But O
+what O
+sets O
+sintering S-MANP
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+from O
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+fully O
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+powder S-MATE
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+the O
+point O
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+the O
+powder S-MATE
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+together O
+on O
+a O
+molecular O
+level O
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+
+The O
+latest O
+SLS S-MANP
+machines S-MACEQ
+offer O
+laser B-PARA
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+( O
+in O
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+. O
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+
+The O
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+
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+infiltration S-CONPRI
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+to O
+the O
+steel S-MATE
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+
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+a O
+greater O
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+the O
+PolyJet S-CONPRI
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+. O
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+
+Direct B-MANP
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+( O
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+similar O
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+. O
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+
+The O
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+
+A O
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+manufactured S-CONPRI
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+Z O
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+the O
+powder S-MATE
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+deposited O
+via O
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+. O
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+
+The O
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+. O
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+
+The O
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+EOS S-APPL
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+
+The O
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+an O
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+in O
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+chamber O
+. O
+
+
+DMLS S-MANP
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+make O
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+. O
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+
+Today O
+, O
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+in O
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+the O
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+
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+
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+
+One O
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+
+The O
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+
+In O
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+new O
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+derivative O
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+
+On O
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+
+A O
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+
+Unlike O
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+only O
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+
+This O
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+
+With O
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+
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+
+The O
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+
+Phidias O
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+
+The O
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+reach O
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+30 O
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+
+A O
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+
+The O
+proposed O
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+
+The O
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+
+Close O
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+
+This O
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+a O
+thermoplastic B-MATE
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+
+
+FDM S-MANP
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+. O
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+
+The O
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+object O
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+
+Compared O
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+
+The O
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+
+The O
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+, O
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+a O
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+. O
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+
+FDM S-MANP
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+the O
+most O
+popular O
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+
+The O
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+
+These O
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+
+The O
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+
+All O
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+
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+
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+
+In O
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+
+The O
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+
+This O
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+
+In O
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+
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+
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+
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+
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+
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+
+It O
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+
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+
+It O
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+
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+large O
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+
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+
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+
+It O
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+niche O
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+
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+
+This O
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+
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+selectively O
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+
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+
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+
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+
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+directly O
+related O
+to O
+the O
+AM B-MANP
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+
+For O
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+produced O
+by O
+L-PBF S-MANP
+to O
+be S-MATE
+between O
+4 O
+and O
+14 O
+% O
+. O
+
+
+Simpson O
+gives O
+a O
+more O
+generic O
+overview O
+of O
+post-processing S-CONPRI
+cost O
+for O
+metal B-MANP
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+. O
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+
+3.4 O
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+considerations O
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+considered O
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+process B-CONPRI
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+
+
+Process B-CONPRI
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+most O
+important O
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+manufacturing S-MANP
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+
+Compared O
+to O
+traditional O
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+context O
+changes O
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+, O
+but O
+it O
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+
+Although O
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+highly O
+integrated O
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+automatic O
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+enabling O
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+machine S-MACEQ
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+receiving O
+a O
+design S-FEAT
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+
+In O
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+chain O
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+
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+
+Layer S-PARA
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+packed O
+parts O
+with O
+their O
+support B-FEAT
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+
+In O
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+stage O
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+
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+the O
+material S-MATE
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+taking O
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+layers O
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+
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+
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+
+However O
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+be S-MATE
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+with O
+respect O
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+global O
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+of O
+manufacturing S-MANP
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+
+As S-MATE
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+and O
+geometry S-CONPRI
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+mandatory O
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+the O
+consequences O
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+the O
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+
+Consequently O
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+
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+
+For O
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+
+This O
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+the O
+build B-PARA
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+be S-MATE
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+into O
+several O
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+be S-MATE
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+separately O
+. O
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+
+3.5 O
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+all O
+technologies S-CONPRI
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+AM S-MANP
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+
+This O
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+common O
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+
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+
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+
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+meets O
+many O
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+modern O
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+
+The O
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+
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+
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+
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+
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+
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+
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+
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+
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+
+In O
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+a O
+very O
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+in O
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+
+All O
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+
+Many O
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+
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+
+In O
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+carefully-graded O
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+
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+
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+
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+
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+
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+before O
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+
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+
+Having O
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+
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+
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+
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+
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+
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+
+This O
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+
+3.6 O
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+of O
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+time O
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+that O
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+rather O
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+do O
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+possible O
+. O
+
+
+AM S-MANP
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+now O
+considered O
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+not O
+eliminate O
+them O
+entirely O
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+
+
+Sometimes O
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+the O
+post-process S-CONPRI
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+than O
+in O
+the O
+AM S-MANP
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+itself O
+. O
+
+
+Post-processing S-CONPRI
+tasks O
+can O
+be S-MATE
+broadly O
+divided O
+in O
+terms O
+of O
+those O
+that O
+can O
+require O
+significant O
+manual O
+intervention O
+and O
+those O
+that O
+can O
+be S-MATE
+carried O
+out O
+in O
+a O
+largely O
+automated O
+fashion S-CONPRI
+. O
+
+
+Of O
+course O
+this O
+depends O
+on O
+the O
+available O
+technology S-CONPRI
+to O
+achieve O
+these O
+tasks O
+as S-MATE
+well O
+as S-MATE
+the O
+level O
+of O
+investment O
+, O
+quality S-CONPRI
+issues O
+, O
+volume S-CONPRI
+of O
+production S-MANP
+, O
+etc O
+. O
+
+
+Post-processing S-CONPRI
+can O
+also O
+be S-MATE
+considered O
+in O
+terms O
+of O
+those O
+that O
+need O
+to O
+be S-MATE
+carried O
+out O
+due O
+to O
+the O
+characteristics O
+of O
+the O
+AM B-MANP
+process E-MANP
+used O
+and O
+those O
+that O
+are O
+more O
+aimed O
+at O
+enhancement O
+of O
+the O
+AM B-MACEQ
+parts E-MACEQ
+. O
+
+
+Like O
+with O
+the O
+previous O
+classification S-CONPRI
+, O
+there O
+are O
+overlaps O
+or O
+grey O
+areas S-PARA
+, O
+around O
+where O
+exactly O
+surface B-FEAT
+finish E-FEAT
+fits S-CONPRI
+for O
+example O
+. O
+
+
+This O
+can O
+also O
+form O
+part O
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+the O
+decision O
+making O
+in O
+the O
+process S-CONPRI
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+specific O
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+mainly O
+refer O
+to O
+the O
+chosen O
+build S-PARA
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+and O
+are O
+aimed O
+at O
+providing O
+a O
+consistent O
+quality S-CONPRI
+of O
+output O
+suited O
+to O
+the O
+general O
+application O
+. O
+
+
+Many O
+processes S-CONPRI
+use O
+support B-FEAT
+structures E-FEAT
+which O
+have O
+to O
+be S-MATE
+removed O
+somehow O
+, O
+often O
+requiring O
+further O
+finishing S-MANP
+of O
+regions O
+where O
+the O
+supports S-APPL
+connected O
+with O
+the O
+part O
+. O
+
+
+Build B-CONPRI
+strategies E-CONPRI
+often O
+revolve O
+around O
+minimising O
+the O
+amount O
+of O
+supports S-APPL
+or O
+avoiding O
+key O
+surfaces S-CONPRI
+for O
+aesthetic S-CONPRI
+or O
+accuracy S-CHAR
+reasons O
+. O
+
+
+For O
+many O
+machines S-MACEQ
+, O
+flat O
+and O
+curved B-CONPRI
+surfaces E-CONPRI
+can O
+appear O
+different O
+due O
+to O
+the O
+stair-stepping O
+phenomena O
+. O
+
+
+Abrasive S-MATE
+or O
+chemical O
+finishing S-MANP
+can O
+be S-MATE
+used O
+to O
+make O
+these O
+surfaces S-CONPRI
+appear O
+more O
+uniform O
+. O
+
+
+A O
+further O
+post-processing S-CONPRI
+task O
+can O
+revolve O
+around O
+excess O
+material S-MATE
+that O
+may O
+be S-MATE
+adhering O
+to O
+the O
+part O
+surfaces S-CONPRI
+. O
+
+
+This O
+may O
+be S-MATE
+a O
+surrounding O
+material S-MATE
+that O
+protects O
+these O
+surfaces S-CONPRI
+or O
+they O
+may O
+be S-MATE
+residual O
+material S-MATE
+due O
+to O
+inconsistencies O
+in O
+the O
+process S-CONPRI
+, O
+similar O
+to O
+flash S-MATE
+in O
+moulding S-CONPRI
+operations O
+. O
+
+
+Although O
+specific O
+to O
+powder-based O
+AM B-MANP
+technology E-MANP
+, O
+pore-filling O
+and O
+densification S-MANP
+can O
+also O
+be S-MATE
+application O
+specific O
+in O
+terms O
+of O
+the O
+material S-MATE
+chosen O
+to O
+create O
+a O
+fully B-PARA
+dense E-PARA
+part O
+. O
+
+
+Densification S-MANP
+can O
+also O
+be S-MATE
+in O
+the O
+form O
+of O
+a O
+furnace S-MACEQ
+cycle O
+, O
+perhaps O
+using O
+hot B-MANP
+isostatic I-MANP
+pressing E-MANP
+. O
+
+
+Since O
+some O
+processes S-CONPRI
+can O
+be S-MATE
+slightly O
+heterogeneous S-CONPRI
+in O
+nature O
+, O
+accounting O
+for O
+shrinkage S-CONPRI
+may O
+require O
+careful O
+preparation O
+and O
+difficult O
+to O
+precisely O
+control O
+. O
+
+
+Metal B-MANP
+AM E-MANP
+parts O
+in O
+particular O
+are O
+commonly O
+used O
+as S-MATE
+fully O
+functional O
+parts O
+. O
+
+
+Choice O
+of O
+metal S-MATE
+as S-MATE
+a O
+part O
+material S-MATE
+often O
+relates O
+to O
+part O
+strength S-PRO
+and O
+while O
+precision S-CHAR
+can O
+represent O
+a O
+problem O
+. O
+
+
+Finish B-MANP
+machining E-MANP
+of O
+key O
+surfaces S-CONPRI
+is O
+often O
+required O
+, O
+much O
+in O
+the O
+same O
+way O
+as S-MATE
+we O
+would O
+treat O
+a O
+casting S-MANP
+. O
+
+
+In O
+these O
+specific O
+regions O
+it O
+may O
+be S-MATE
+appropriate O
+to O
+grow O
+some O
+of O
+these O
+surfaces S-CONPRI
+in O
+the O
+design S-FEAT
+phase O
+to O
+provide O
+sufficient O
+machining B-PARA
+allowance E-PARA
+to O
+ensure O
+high O
+quality S-CONPRI
+, O
+accurate S-CHAR
+results O
+. O
+
+
+It O
+can O
+be S-MATE
+argued O
+that O
+there O
+will O
+be S-MATE
+fewer O
+of O
+these O
+surfaces S-CONPRI
+to O
+finish O
+since O
+it O
+is O
+common O
+thinking O
+that O
+AM S-MANP
+allows O
+for O
+part B-CONPRI
+consolidation E-CONPRI
+due O
+to O
+the O
+ability O
+to O
+create O
+internalised O
+features O
+. O
+
+
+Although O
+it O
+is O
+quite O
+possible O
+to O
+print S-MANP
+features O
+like O
+holes O
+and O
+screw-threads O
+using O
+AM S-MANP
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+the O
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+on O
+such O
+features O
+can O
+be S-MATE
+very O
+stringent O
+and O
+beyond O
+the O
+capacity S-CONPRI
+of O
+the O
+AM B-MANP
+technology E-MANP
+used O
+. O
+
+
+It O
+may O
+be S-MATE
+possible O
+to O
+save O
+material S-MATE
+by O
+printing O
+a O
+hole O
+but O
+the O
+time O
+taken O
+to O
+finish O
+a O
+partially-made O
+hole O
+may O
+be S-MATE
+the O
+same O
+, O
+or O
+even O
+longer O
+, O
+than O
+to O
+drill S-MACEQ
+a O
+complete O
+hole O
+in O
+a O
+blank S-MATE
+space O
+. O
+
+
+This O
+may O
+be S-MATE
+even O
+more O
+relevant O
+if O
+the O
+hole O
+contained O
+a O
+screw B-FEAT
+thread E-FEAT
+. O
+
+
+Again O
+, O
+it O
+can O
+be S-MATE
+argued O
+that O
+this O
+adds O
+complexity S-CONPRI
+to O
+the O
+process S-CONPRI
+decision-making O
+, O
+but O
+it O
+is O
+pertinent O
+when O
+relating O
+to O
+heavily O
+industrial S-APPL
+applications O
+. O
+
+
+Coatings S-APPL
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+go S-MATE
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+simple S-MANP
+paint O
+jobs O
+to O
+improve O
+aesthetics O
+and O
+seal O
+against O
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+through O
+to O
+providing O
+significant O
+functional O
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+, O
+including O
+bioactive B-CONPRI
+features E-CONPRI
+. O
+
+
+These O
+tasks O
+may O
+require O
+significantly O
+specialised O
+facilities O
+to O
+those O
+used O
+in O
+other O
+production S-MANP
+steps O
+and O
+as S-MATE
+such O
+may O
+be S-MATE
+outsourced O
+. O
+
+
+This O
+could O
+also O
+be S-MATE
+the O
+case O
+with O
+other O
+forms O
+of O
+chemical O
+and O
+heat B-MANP
+treatment E-MANP
+. O
+
+
+Many O
+AM B-MACEQ
+parts E-MACEQ
+can O
+include O
+complex O
+internal O
+or O
+difficult O
+to O
+reach O
+features O
+. O
+
+
+Should O
+these O
+features O
+require O
+finishing S-MANP
+, O
+it O
+may O
+be S-MATE
+somewhat O
+difficult O
+to O
+achieve O
+a O
+stable O
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+, O
+even O
+when O
+using O
+automated O
+techniques O
+. O
+
+
+Some O
+methods O
+are O
+under O
+development O
+to O
+address O
+these O
+issues O
+but O
+more O
+effort O
+could O
+be S-MATE
+made O
+and O
+in O
+fact O
+most O
+methods O
+for O
+surface B-MANP
+finishing E-MANP
+are O
+highly O
+manual O
+in O
+nature O
+. O
+
+
+3.7 O
+AM S-MANP
+quality O
+, O
+inspection S-CHAR
+and O
+certification O
+Many O
+AM S-MANP
+applications O
+can O
+be S-MATE
+found O
+in O
+highly O
+regulated O
+industries S-APPL
+, O
+like O
+aerospace S-APPL
+and O
+medicine S-CONPRI
+. O
+
+
+This O
+is O
+even O
+the O
+case O
+within O
+the O
+medical B-APPL
+industry E-APPL
+where O
+one O
+might O
+expect O
+such O
+parts O
+to O
+be S-MATE
+customised O
+to O
+suit O
+a O
+patient O
+'s O
+needs O
+and O
+anatomy O
+. O
+
+
+Quality B-CONPRI
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+, O
+inspection S-CHAR
+and O
+certification O
+would O
+therefore O
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+in O
+a O
+similar O
+fashion S-CONPRI
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+conventionally O
+manufactured S-CONPRI
+parts O
+. O
+
+
+Validation S-CONPRI
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+these O
+cases O
+is O
+as S-MATE
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+about O
+ensuring O
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+the O
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+the O
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+chain E-CONPRI
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+it O
+is O
+about O
+the O
+functionality O
+of O
+the O
+part O
+. O
+
+
+The O
+US O
+Federal O
+Food O
+and O
+Drug O
+Administration O
+is O
+widely O
+regarded O
+as S-MATE
+a O
+key O
+standards S-CONPRI
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+around O
+the O
+world O
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+many O
+other O
+countries O
+base O
+their O
+own O
+medical S-APPL
+standards O
+on O
+the O
+FDA S-MANS
+. O
+
+
+In O
+2017 O
+the O
+FDA S-MANS
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+guidelines O
+related O
+to O
+technical O
+use O
+of O
+AM S-MANP
+in O
+medical B-APPL
+devices E-APPL
+. O
+
+
+These O
+guidelines O
+cover O
+aspects O
+related O
+to O
+AM-based O
+design S-FEAT
+of O
+medical B-APPL
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+as S-MATE
+well O
+as S-MATE
+how O
+they O
+are O
+manufactured S-CONPRI
+and O
+validated O
+. O
+
+
+Certification O
+of O
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+required O
+if O
+there O
+is O
+a O
+medium O
+to O
+high O
+risk O
+potential O
+to O
+the O
+user O
+. O
+
+
+All O
+implantable B-MACEQ
+devices E-MACEQ
+would O
+be S-MATE
+Class O
+II O
+or O
+Class O
+III O
+, O
+whilst O
+AM S-MANP
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+foot B-MACEQ
+orthotics E-MACEQ
+are O
+class O
+I O
+, O
+requiring O
+no O
+premarket O
+notification O
+to O
+prove O
+they O
+have O
+been O
+clinically O
+tested O
+certification O
+) O
+. O
+
+
+The O
+medical B-APPL
+device E-APPL
+manufacturer S-CONPRI
+Stryker O
+released O
+their O
+Spine O
+Tritanium O
+PL B-MATE
+Cage E-MATE
+around O
+2016 O
+. O
+
+
+AM S-MANP
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+used O
+to O
+create O
+a O
+complex O
+porous S-PRO
+geometry S-CONPRI
+of O
+titanium S-MATE
+that O
+aims O
+to O
+promote O
+bone B-CONPRI
+ingrowth E-CONPRI
+in O
+a O
+lumbar B-CONPRI
+spine I-CONPRI
+fusion I-CONPRI
+process E-CONPRI
+. O
+
+
+It O
+is O
+possible O
+that O
+introduction O
+of O
+this O
+device O
+may O
+have O
+been O
+premature O
+as S-MATE
+it O
+is O
+believed O
+that O
+more O
+experimental S-CONPRI
+work O
+is O
+needed O
+to O
+establish O
+the O
+boundaries S-FEAT
+for O
+fatigue S-PRO
+in O
+AM S-MANP
+lattice O
+structures O
+. O
+
+
+It O
+should O
+be S-MATE
+noted O
+that O
+similar O
+porous S-PRO
+and O
+irregular O
+lattice B-FEAT
+structures E-FEAT
+have O
+been O
+used O
+in O
+100,000s O
+of O
+successful O
+acetabular O
+hip B-APPL
+implant E-APPL
+cases O
+. O
+
+
+This O
+issue O
+of O
+possible O
+failure S-CONPRI
+will O
+be S-MATE
+even O
+more O
+important O
+should O
+the O
+device O
+have O
+a O
+customisable O
+geometry S-CONPRI
+. O
+
+
+The O
+FDA S-MANS
+refers O
+to O
+these O
+as S-MATE
+Customised O
+or O
+Humanitarian-use O
+devices O
+. O
+
+
+These O
+must O
+also O
+be S-MATE
+limited O
+in O
+number O
+and O
+subject O
+to O
+significant O
+medical S-APPL
+board O
+scrutiny O
+. O
+
+
+Medical S-APPL
+authorities O
+are O
+currently O
+at O
+a O
+significant O
+cross-road O
+as S-MATE
+to O
+how O
+to O
+provide O
+custom B-APPL
+implants E-APPL
+for O
+more O
+widespread O
+use O
+. O
+
+
+Aerospace S-APPL
+certification O
+, O
+through O
+the O
+Federal O
+Aviation O
+Authority O
+, O
+also O
+appears O
+to O
+be S-MATE
+at O
+a O
+similar O
+cross-road O
+. O
+
+
+However O
+, O
+it O
+is O
+noted O
+that O
+many O
+parts O
+already O
+in O
+use O
+could O
+be S-MATE
+repaired O
+when O
+damaged O
+using O
+AM B-MANP
+techniques E-MANP
+, O
+most O
+specifically O
+using O
+Directed B-MANP
+Energy I-MANP
+Deposition E-MANP
+. O
+
+
+Many O
+safety S-CONPRI
+critical O
+parts O
+, O
+like O
+turbine B-APPL
+blades E-APPL
+, O
+could O
+be S-MATE
+repaired O
+in O
+this O
+way O
+. O
+
+
+Emphasis O
+must O
+therefore O
+be S-MATE
+on O
+the O
+AM B-MANP
+process E-MANP
+to O
+ensure O
+that O
+functionality O
+is O
+maintained O
+to O
+a O
+suitable O
+standard S-CONPRI
+. O
+
+
+For O
+example O
+Air O
+New O
+Zealand O
+are O
+saving O
+significant O
+repair B-PARA
+costs E-PARA
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+making O
+their O
+own O
+replacement O
+seat O
+tray-tables O
+using O
+materials S-CONPRI
+like O
+the O
+flame-retardant O
+ULTEM O
+9085 O
+polymer B-MATE
+material E-MATE
+from O
+Stratasys S-APPL
+. O
+
+
+This O
+is O
+just O
+part O
+of O
+a O
+much O
+wider O
+push O
+to O
+demonstrate O
+a O
+sustainable S-CONPRI
+industry S-APPL
+for O
+AM S-MANP
+in O
+aerospace S-APPL
+. O
+
+
+Many O
+of O
+the O
+above O
+issues O
+for O
+medical S-APPL
+and O
+aerospace S-APPL
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+a O
+more O
+general O
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+within O
+the O
+standards S-CONPRI
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+development O
+by O
+ISO S-MANS
+Technical O
+Committee O
+261 O
+in O
+conjunction O
+with O
+the O
+ASTM O
+F42 O
+Group O
+. O
+
+
+Numerous O
+techniques O
+, O
+like O
+the O
+printing O
+of O
+test O
+coupons O
+alongside O
+critical O
+components S-MACEQ
+, O
+machine B-PARA
+calibration E-PARA
+and O
+material S-MATE
+storage O
+, O
+etc O
+. O
+
+
+This O
+has O
+led S-APPL
+to O
+significant O
+improvements O
+in O
+process B-CONPRI
+monitoring E-CONPRI
+within O
+industrial S-APPL
+scale O
+AM B-MACEQ
+machines E-MACEQ
+. O
+
+
+Many O
+polymer-based O
+systems O
+have O
+camera S-MACEQ
+monitoring O
+that O
+allow O
+determining O
+the O
+build B-PARA
+status E-PARA
+and O
+remote O
+intervention O
+if O
+problems O
+can O
+be S-MATE
+seen O
+. O
+
+
+Many O
+metal S-MATE
+L-PBF B-MACEQ
+systems E-MACEQ
+also O
+have O
+optional O
+laser B-PARA
+power E-PARA
+and O
+melt-pool O
+sensing S-APPL
+to O
+determine O
+the O
+state O
+of O
+part O
+with O
+the O
+possibility O
+of O
+detecting O
+a O
+failure S-CONPRI
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+it O
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+structural B-CONPRI
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+AM B-MANP
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+More O
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+, O
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+extent O
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+
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+benefits O
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+
+In O
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+4.1 O
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+obtain O
+the O
+expected O
+mechanical B-CONPRI
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+minimum O
+material S-MATE
+use O
+. O
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+
+The O
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+numerical O
+analysis O
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+design S-FEAT
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+iterative O
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+, O
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+gradient O
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+non-gradient B-CONPRI
+discrete I-CONPRI
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+. O
+
+
+Traditionally O
+, O
+TO O
+is O
+driven O
+by O
+an O
+objective O
+function O
+, O
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+a O
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+predefined O
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+as S-MATE
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+
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+to O
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+
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+so O
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+at O
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+minimal O
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+
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+
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+both O
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+
+As S-MATE
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+, O
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+as S-MATE
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+, O
+general O
+applicability O
+, O
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+use O
+, O
+etc O
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+
+Many O
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+them O
+only O
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+
+When O
+introducing O
+extra O
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+constraints O
+such O
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+, O
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+features O
+, O
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+heat-transfer O
+, O
+thermal O
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+into O
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+, O
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+would O
+result O
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+more O
+complex O
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+
+This O
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+solutionwith O
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+
+Attracted O
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+great O
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+AM S-MANP
+, O
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+. O
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+
+Therefore O
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+towards O
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+This O
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+This O
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+
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+
+For O
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+
+Then O
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+
+In O
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+
+2D S-CONPRI
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+3D S-CONPRI
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+
+Taking O
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+
+This O
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+
+The O
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+Readers O
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+To O
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+
+However O
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+In O
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+`For O
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+In O
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+
+Even O
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+totally O
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+To O
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+a O
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+
+In O
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+
+Similar O
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+However O
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+
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+
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+
+Therefore O
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+
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+
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+
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+
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+
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+
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+
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+
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+This O
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+
+In O
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+in O
+traditional O
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+
+To O
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+simultaneously O
+design S-FEAT
+, O
+structurally O
+optimize O
+and O
+appraise O
+the O
+manufacturability S-CONPRI
+of O
+parts O
+produced O
+by O
+additive B-MANP
+manufacturing E-MANP
+. O
+
+
+Voxels S-CONPRI
+are O
+used O
+to O
+carry O
+the O
+design B-CONPRI
+rules E-CONPRI
+and O
+manufacturing B-CONPRI
+constraints E-CONPRI
+for O
+reasoning O
+and O
+combination O
+during O
+the O
+geometry B-CONPRI
+evolution E-CONPRI
+process O
+. O
+
+
+However O
+, O
+this O
+method O
+considers O
+support B-FEAT
+structures E-FEAT
+as S-MATE
+the O
+only O
+AM S-MANP
+constraint O
+and O
+has O
+difficulty O
+to O
+include O
+more O
+. O
+
+
+For O
+generative B-ENAT
+design E-ENAT
+for O
+AM S-MANP
+, O
+there O
+is O
+still O
+a O
+lot O
+of O
+work O
+to O
+do O
+to O
+include O
+more O
+AM S-MANP
+constraints O
+and O
+develop O
+more O
+efficient O
+decision O
+making O
+tools S-MACEQ
+to O
+help O
+designers O
+define O
+optimization S-CONPRI
+criteria O
+and O
+candidate O
+solution S-CONPRI
+ranking O
+schemes O
+. O
+
+
+Some O
+commercial O
+tools S-MACEQ
+are O
+now O
+available O
+however O
+. O
+
+
+On O
+the O
+other O
+hand O
+, O
+when O
+doing O
+structure B-FEAT
+design E-FEAT
+via O
+generative B-ENAT
+design E-ENAT
+methods O
+, O
+the O
+global O
+optimum O
+and O
+computational O
+cost O
+should O
+be S-MATE
+given O
+attention O
+. O
+
+
+Recently O
+, O
+researchers O
+began O
+to O
+combine O
+TO O
+with O
+generative B-ENAT
+models E-ENAT
+, O
+e.g. O
+, O
+generative B-ENAT
+adversarial I-ENAT
+networks E-ENAT
+, O
+and O
+proposed O
+a O
+new O
+concept O
+, O
+deep B-FEAT
+generative I-FEAT
+design E-FEAT
+, O
+which O
+owns O
+the O
+learning O
+capability O
+from O
+the O
+iteration O
+process S-CONPRI
+and O
+existing O
+design S-FEAT
+data S-CONPRI
+. O
+
+
+These O
+concepts O
+hold O
+the O
+potential O
+to O
+better O
+integrate O
+existing O
+AM S-MANP
+processing O
+knowledge O
+into O
+the O
+generative B-ENAT
+design E-ENAT
+procedure O
+to O
+populate O
+and O
+explore O
+more O
+qualified O
+AM S-MANP
+design O
+solutions O
+. O
+
+
+Certainly O
+, O
+generative B-ENAT
+design E-ENAT
+is O
+not O
+only O
+used O
+for O
+topology B-FEAT
+optimization E-FEAT
+but O
+also O
+can O
+be S-MATE
+applied O
+to O
+form O
+synthesis O
+, O
+lattice S-CONPRI
+and O
+surface B-FEAT
+structure E-FEAT
+optimization S-CONPRI
+and O
+trabecular B-FEAT
+structures E-FEAT
+as S-MATE
+a O
+way O
+to O
+explore O
+more O
+design B-CONPRI
+freedom E-CONPRI
+using O
+AM S-MANP
+. O
+
+
+4.3 O
+Lattice B-FEAT
+structure E-FEAT
+filling O
+Directly O
+removing O
+or O
+adding O
+material S-MATE
+in O
+the O
+design B-CONPRI
+space E-CONPRI
+to O
+search O
+for O
+the O
+global O
+optimal O
+material S-MATE
+topology O
+solution S-CONPRI
+is O
+common O
+to O
+TO O
+and O
+generative B-ENAT
+design E-ENAT
+methods O
+and O
+, O
+as S-MATE
+stated O
+above O
+, O
+there O
+are O
+many O
+difficulties O
+. O
+
+
+As S-MATE
+a O
+compromise O
+, O
+generative B-ENAT
+design E-ENAT
+can O
+include O
+human O
+knowledge O
+to O
+interactively O
+select O
+the O
+candidate O
+solutions O
+so O
+as S-MATE
+to O
+reduce O
+the O
+problem O
+complexity S-CONPRI
+. O
+
+
+Therefore O
+, O
+this O
+is O
+an O
+indirect O
+lightweight S-CONPRI
+design S-FEAT
+method O
+for O
+AM S-MANP
+, O
+which O
+is O
+also O
+called O
+lattice B-CONPRI
+configuration E-CONPRI
+, O
+18 O
+. O
+
+
+To O
+obtain O
+lattice B-FEAT
+structures E-FEAT
+, O
+generally O
+we O
+have O
+two O
+approaches O
+: O
+1 O
+. O
+
+
+Homogenization S-MANP
+and O
+2 O
+. O
+
+
+Density S-PRO
+based O
+mapping O
+. O
+
+
+The O
+former O
+homogenizes O
+the O
+lattice B-FEAT
+structure E-FEAT
+as S-MATE
+representative O
+volume S-CONPRI
+elements S-MATE
+, O
+like O
+solid O
+material S-MATE
+. O
+
+
+The O
+lattice B-FEAT
+structures E-FEAT
+are O
+similar O
+to O
+the O
+micro O
+porous S-PRO
+for O
+the O
+traditional O
+solid O
+structure S-CONPRI
+in O
+homogenized B-PRO
+volumes E-PRO
+. O
+
+
+In O
+this O
+way O
+, O
+special O
+properties S-CONPRI
+should O
+be S-MATE
+assigned O
+to O
+the O
+representative O
+volumes O
+and O
+then O
+we O
+can O
+apply O
+traditional O
+TO O
+or O
+other O
+structure B-CONPRI
+optimization E-CONPRI
+methods O
+to O
+operate O
+the O
+special O
+volumes O
+. O
+
+
+Representative O
+researches O
+that O
+apply O
+this O
+method O
+can O
+be S-MATE
+found O
+in O
+and O
+19 O
+illustrates O
+the O
+general O
+workflow S-CONPRI
+. O
+
+
+The O
+second O
+approach O
+maps O
+the O
+density S-PRO
+values O
+obtained O
+from O
+non-penalized O
+TO O
+results O
+onto O
+the O
+explicit O
+predefined O
+lattice B-FEAT
+structures E-FEAT
+with O
+optional O
+adaptation O
+to O
+improve O
+the O
+approximation O
+accuracy S-CHAR
+of O
+mechanical B-CONPRI
+response E-CONPRI
+. O
+
+
+Based O
+on O
+this O
+approach O
+, O
+uniform O
+or O
+graded O
+lattice B-FEAT
+structures E-FEAT
+can O
+be S-MATE
+obtained O
+. O
+
+
+Example O
+studies O
+can O
+be S-MATE
+found O
+in O
+. O
+
+
+20 O
+shows O
+an O
+example O
+where O
+different O
+predefined O
+lattice B-FEAT
+structures E-FEAT
+are O
+used O
+to O
+map O
+the O
+solid O
+volume S-CONPRI
+TO O
+contours S-FEAT
+. O
+
+
+Although O
+the O
+two O
+appraoches O
+are O
+not O
+hard O
+to O
+understand O
+, O
+the O
+operation O
+and O
+optimization S-CONPRI
+of O
+lattice B-FEAT
+structures E-FEAT
+is O
+quite O
+complicated O
+, O
+especially O
+for O
+large O
+size O
+structure B-FEAT
+design E-FEAT
+. O
+
+
+The O
+first O
+problem O
+is O
+the O
+representation/digitalization O
+of O
+lattice B-FEAT
+structures E-FEAT
+. O
+
+
+Usually O
+, O
+solid O
+representation O
+or O
+surface S-CONPRI
+representation O
+can O
+be S-MATE
+used O
+for O
+individual O
+lattice B-FEAT
+units E-FEAT
+. O
+
+
+But O
+when O
+filled O
+into O
+solid B-MACEQ
+hulls E-MACEQ
+, O
+the O
+number O
+of O
+lattice B-FEAT
+units E-FEAT
+is O
+very O
+big O
+, O
+which O
+makes O
+the O
+CAD B-MANS
+file E-MANS
+difficult O
+to O
+operate O
+, O
+including O
+sweeping O
+, O
+meshing/mapping O
+and O
+tessellation S-FEAT
+. O
+
+
+Secondly O
+, O
+when O
+doing O
+numerical B-ENAT
+simulation E-ENAT
+, O
+the O
+computation S-CONPRI
+cost O
+is O
+much O
+higher O
+since O
+many O
+more O
+finite B-CONPRI
+element E-CONPRI
+units O
+are O
+required O
+. O
+
+
+Thirdly O
+, O
+when O
+filling O
+lattice B-FEAT
+structures E-FEAT
+into O
+solid B-MACEQ
+hulls E-MACEQ
+, O
+one O
+needs O
+to O
+use O
+uniform O
+lattice S-CONPRI
+in O
+trimming S-MANP
+or O
+non-uniform O
+lattice S-CONPRI
+with O
+conformal O
+interface S-CONPRI
+, O
+which O
+depends O
+on O
+specific O
+design S-FEAT
+cases O
+. O
+
+
+Some O
+researchers O
+stated O
+that O
+conformal B-FEAT
+lattice I-FEAT
+structures E-FEAT
+have O
+better O
+structural B-CHAR
+performance E-CHAR
+than O
+that O
+of O
+uniformed O
+. O
+
+
+However O
+, O
+the O
+operation O
+of O
+conformal B-FEAT
+lattice E-FEAT
+is O
+more O
+complicated O
+and O
+more O
+difficult O
+to O
+control O
+the O
+manufacturability S-CONPRI
+since O
+they O
+are O
+not O
+, O
+like O
+uniform O
+lattices S-CONPRI
+usually O
+are O
+, O
+derived O
+from O
+benchmarking O
+results O
+. O
+
+
+After O
+that O
+, O
+the O
+computation S-CONPRI
+cost O
+is O
+a O
+big O
+issue O
+, O
+not O
+only O
+for O
+the O
+representation O
+, O
+but O
+also O
+for O
+simulation S-ENAT
+and O
+manufacturing S-MANP
+. O
+
+
+That O
+is O
+why O
+some O
+researchers O
+proposed O
+to O
+use O
+kernel O
+or O
+symbolic O
+representations O
+for O
+lattice B-FEAT
+units E-FEAT
+. O
+
+
+Finally O
+, O
+the O
+most O
+important O
+challenge O
+is O
+how O
+to O
+obtain O
+the O
+global O
+optimum O
+when O
+using O
+lattice B-FEAT
+structures E-FEAT
+. O
+
+
+The O
+approximation O
+process S-CONPRI
+further O
+reduces O
+the O
+original O
+design B-CONPRI
+space E-CONPRI
+and O
+introduces O
+more O
+errors S-CONPRI
+. O
+
+
+Predefined O
+and O
+benchmarked O
+limited O
+lattice B-FEAT
+structures E-FEAT
+with O
+fixed O
+parameters S-CONPRI
+are O
+just O
+a O
+subset O
+of O
+the O
+design S-FEAT
+variants O
+. O
+
+
+Actually O
+, O
+even O
+for O
+predefined O
+lattice B-FEAT
+units E-FEAT
+, O
+there O
+are O
+more O
+parameters S-CONPRI
+that O
+can O
+be S-MATE
+modified O
+and O
+adjusted O
+to O
+specific O
+design S-FEAT
+cases O
+. O
+
+
+Currently O
+, O
+many O
+optimization S-CONPRI
+studies O
+for O
+lattice B-FEAT
+structures E-FEAT
+are O
+only O
+limited O
+to O
+density S-PRO
+, O
+represented O
+by O
+strut B-PARA
+diameter E-PARA
+, O
+and O
+very O
+little O
+work O
+focuses O
+on O
+parameter S-CONPRI
+optimization S-CONPRI
+and O
+computation S-CONPRI
+benchmarking O
+for O
+large O
+lattice B-FEAT
+structure I-FEAT
+design E-FEAT
+cases O
+. O
+
+
+Therefore O
+, O
+to O
+be S-MATE
+practical O
+, O
+current O
+methods O
+and O
+tools S-MACEQ
+from O
+academic O
+codes O
+or O
+commercial O
+software S-CONPRI
+tools O
+all O
+adopt O
+knowledge O
+based O
+methods O
+with O
+TO O
+methods O
+for O
+lattice B-FEAT
+filling E-FEAT
+. O
+
+
+Usually O
+, O
+a O
+lattice S-CONPRI
+library O
+is O
+built O
+to O
+store O
+predefined O
+lattice B-FEAT
+units E-FEAT
+, O
+benchmarked O
+with O
+numerical B-ENAT
+simulation E-ENAT
+or O
+manufacturability S-CONPRI
+analysis O
+, O
+and O
+then O
+a O
+limited O
+set S-APPL
+of O
+control O
+options O
+, O
+concerning O
+the O
+lattice B-FEAT
+unit I-FEAT
+size E-FEAT
+, O
+strut B-PARA
+diameter E-PARA
+, O
+layout S-CONPRI
+orientation O
+, O
+etc. O
+, O
+are O
+available O
+for O
+the O
+filling O
+operation O
+. O
+
+
+This O
+is O
+the O
+main O
+workflow S-CONPRI
+of O
+current O
+tools S-MACEQ
+. O
+
+
+As S-MATE
+said O
+before O
+, O
+although O
+relatively O
+small O
+or O
+medium O
+sized O
+lattice B-FEAT
+structures E-FEAT
+can O
+be S-MATE
+obtained O
+, O
+one O
+not O
+only O
+sacrifices O
+the O
+stiffness S-PRO
+but O
+also O
+it O
+may O
+be S-MATE
+more O
+difficult O
+to O
+search O
+for O
+the O
+original O
+global O
+optimal O
+lightweight S-CONPRI
+design S-FEAT
+solution O
+. O
+
+
+If O
+one O
+only O
+considers O
+the O
+lightweight S-CONPRI
+effect O
+in O
+the O
+design S-FEAT
+, O
+lattice B-FEAT
+filling E-FEAT
+may O
+not O
+be S-MATE
+the O
+optimal O
+choice O
+. O
+
+
+However O
+, O
+lattice B-FEAT
+structures E-FEAT
+can O
+bring O
+other O
+benefits O
+, O
+e.g O
+. O
+
+
+energy B-CHAR
+absorption E-CHAR
+and O
+heat B-CONPRI
+conduction E-CONPRI
+that O
+solid O
+structures O
+may O
+not O
+have O
+. O
+
+
+This O
+would O
+be S-MATE
+an O
+important O
+factor O
+to O
+encourage O
+research S-CONPRI
+and O
+practice O
+in O
+the O
+lattice B-CONPRI
+domain E-CONPRI
+. O
+
+
+5 O
+Tools S-MACEQ
+and O
+methods O
+for O
+optimizing O
+surface B-FEAT
+structure E-FEAT
+As S-MATE
+discussed O
+above O
+, O
+the O
+global O
+optimal O
+for O
+structure B-FEAT
+design E-FEAT
+is O
+usually O
+hard O
+to O
+obtain O
+. O
+
+
+Similar O
+to O
+lattice B-FEAT
+structures E-FEAT
+, O
+which O
+are O
+made O
+artificially O
+, O
+natural O
+porous S-PRO
+structures O
+become O
+a O
+set S-APPL
+of O
+special O
+elements S-MATE
+to O
+deal O
+with O
+specific O
+design S-FEAT
+requirements O
+. O
+
+
+Examples O
+include O
+among O
+others O
+lightweight S-CONPRI
+infill S-PARA
+, O
+porous B-FEAT
+scaffolds E-FEAT
+, O
+energy O
+absorbers O
+, O
+micro-reactors S-MACEQ
+, O
+heat B-MACEQ
+conductors E-MACEQ
+, O
+or O
+self-adaptating O
+structures O
+. O
+
+
+These O
+structures/functionalities O
+have O
+been O
+known O
+for O
+some O
+time O
+, O
+but O
+due O
+to O
+the O
+ability O
+of O
+AM S-MANP
+to O
+produce O
+these O
+complex B-CONPRI
+structures E-CONPRI
+, O
+they O
+now O
+become O
+part O
+of O
+the O
+solution S-CONPRI
+principles O
+that O
+can O
+be S-MATE
+applied O
+by O
+the O
+product O
+designer O
+. O
+
+
+Hence O
+, O
+the O
+mimicking O
+and O
+post-processing S-CONPRI
+of O
+natural O
+inspired O
+or O
+randomly O
+generated O
+complex O
+topologies S-CONPRI
+become O
+a O
+new O
+design S-FEAT
+practice O
+, O
+which O
+is O
+called O
+bio-inspired S-CONPRI
+or O
+biomimetic B-FEAT
+design E-FEAT
+. O
+
+
+Its O
+goal O
+is O
+to O
+generate O
+either O
+lightweight B-MACEQ
+structures E-MACEQ
+with O
+unexpected O
+mechanical B-CONPRI
+properties E-CONPRI
+, O
+similar O
+to O
+the O
+lightweight S-CONPRI
+design S-FEAT
+methods O
+mentioned O
+in O
+the O
+last O
+section O
+, O
+or O
+multi-functional O
+surface B-FEAT
+structures E-FEAT
+as S-MATE
+addressed O
+here O
+. O
+
+
+This O
+type O
+of O
+design S-FEAT
+is O
+more O
+difficult O
+than O
+that O
+of O
+relatively O
+regular O
+or O
+conformal O
+periodic O
+lattice B-FEAT
+structures E-FEAT
+. O
+
+
+Hence O
+, O
+the O
+design S-FEAT
+and O
+simulation S-ENAT
+focuses O
+more O
+on O
+the O
+form O
+and O
+shape O
+of O
+the O
+surfaces S-CONPRI
+while O
+the O
+mechanical B-CONPRI
+properties E-CONPRI
+and O
+AM S-MANP
+constraints O
+are O
+hard O
+to O
+consider O
+due O
+to O
+their O
+extreme O
+complexity S-CONPRI
+. O
+
+
+Generally O
+, O
+two O
+design S-FEAT
+approaches O
+, O
+direct/indirect O
+reproduction O
+of O
+natural O
+topologies S-CONPRI
+via O
+reverse B-CONPRI
+engineering E-CONPRI
+and O
+generic O
+bio-inspiration S-CONPRI
+using O
+design B-CONPRI
+rules E-CONPRI
+or O
+guidelines O
+, O
+are O
+conducted O
+in O
+this O
+domain S-CONPRI
+. O
+
+
+Driven O
+by O
+the O
+wide O
+application O
+in O
+the O
+medical S-APPL
+domain S-CONPRI
+, O
+scaffolds S-FEAT
+and O
+implants S-APPL
+usually O
+require O
+similar O
+internal O
+surface B-FEAT
+topologies E-FEAT
+to O
+the O
+natural O
+structures O
+they O
+are O
+mimicing O
+. O
+
+
+cell S-APPL
+spreading O
+, O
+strength S-PRO
+distribution S-CONPRI
+. O
+
+
+The O
+main O
+methods O
+to O
+generate O
+irregular O
+porous S-PRO
+structures O
+with O
+complex O
+internal O
+surface B-FEAT
+topologies E-FEAT
+are O
+either O
+filling O
+or O
+hollowing O
+materials S-CONPRI
+from O
+an O
+initial O
+design S-FEAT
+via O
+specific O
+algorithms S-CONPRI
+. O
+
+
+A O
+representative O
+filling O
+method O
+is O
+Triply B-CONPRI
+Periodic I-CONPRI
+Minimal I-CONPRI
+Surface E-CONPRI
+, O
+which O
+is O
+an O
+implicit B-FEAT
+surface E-FEAT
+with O
+intricate O
+structures O
+. O
+
+
+Researchers O
+add O
+different O
+operation B-ENAT
+algorithms E-ENAT
+to O
+do O
+the O
+filling O
+with O
+these O
+surface S-CONPRI
+units O
+so O
+as S-MATE
+to O
+approximate O
+the O
+original O
+CAD B-ENAT
+model E-ENAT
+'s O
+skin O
+. O
+
+
+For O
+the O
+hollowing O
+process S-CONPRI
+, O
+sub-volumes O
+are O
+generated O
+via O
+a O
+set S-APPL
+of O
+specific O
+algorithms S-CONPRI
+within O
+the O
+original O
+3D S-CONPRI
+CAD O
+model S-CONPRI
+and O
+used O
+to O
+do O
+Boolean B-ENAT
+operations E-ENAT
+. O
+
+
+A O
+shape O
+function O
+is O
+applied O
+in O
+to O
+design S-FEAT
+a O
+pore S-PRO
+model S-CONPRI
+and O
+then O
+a O
+subtractive S-MANP
+Boolean B-ENAT
+operation E-ENAT
+is O
+conducted O
+between O
+the O
+pore S-PRO
+and O
+the O
+original O
+solid O
+CAD B-ENAT
+models E-ENAT
+to O
+obtain O
+the O
+final O
+scaffold B-CONPRI
+model E-CONPRI
+. O
+
+
+The O
+process S-CONPRI
+is O
+illustrated O
+in O
+23 O
+. O
+
+
+Similarly O
+, O
+a O
+Voronoi B-FEAT
+tessellation E-FEAT
+method O
+is O
+adopted O
+in O
+to O
+do O
+the O
+material B-CONPRI
+hollowing E-CONPRI
+. O
+
+
+Apart O
+from O
+the O
+internal O
+surface B-FEAT
+structure E-FEAT
+generation O
+, O
+external O
+surface B-FEAT
+structure E-FEAT
+design S-FEAT
+also O
+attracts O
+attention O
+since O
+using O
+AM S-MANP
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+print S-MANP
+complex B-PRO
+shapes E-PRO
+for O
+art S-APPL
+or O
+customized O
+shapes O
+has O
+become O
+popular O
+. O
+
+
+In O
+artistic O
+design S-FEAT
+, O
+T-splines S-FEAT
+and O
+Voronoi B-FEAT
+tessellation E-FEAT
+or O
+predefined O
+pattern S-CONPRI
+bases O
+are O
+commonly O
+used O
+for O
+defining O
+complex O
+surface B-FEAT
+topologies E-FEAT
+. O
+
+
+In O
+, O
+a O
+generative B-ENAT
+design E-ENAT
+method O
+is O
+applied O
+to O
+populate O
+complex O
+surface B-FEAT
+topologies E-FEAT
+via O
+the O
+use O
+of O
+predefined O
+patterns O
+. O
+
+
+A O
+recursive O
+grammar O
+is O
+set S-APPL
+for O
+the O
+generation O
+of O
+solid O
+boundary S-FEAT
+surface O
+models O
+, O
+suitable O
+for O
+a O
+variety O
+of O
+design S-FEAT
+domains O
+. O
+
+
+Freeform B-CONPRI
+3D E-CONPRI
+surface O
+topologies S-CONPRI
+can O
+be S-MATE
+formed O
+by O
+a O
+set S-APPL
+of O
+2-manifold O
+polygonal O
+sub O
+meshes O
+as S-MATE
+shown O
+in O
+24 O
+. O
+
+
+However O
+, O
+the O
+optimization S-CONPRI
+for O
+artistic O
+design S-FEAT
+is O
+not O
+so O
+obvious O
+. O
+
+
+To O
+develop O
+special O
+surface B-FEAT
+structures E-FEAT
+for O
+personalized O
+casts/braces O
+, O
+a O
+new O
+topology B-FEAT
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+method O
+is O
+proposed O
+in O
+. O
+
+
+The O
+novel O
+TO O
+method O
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+based O
+on O
+thin O
+plate O
+elements S-MATE
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+the O
+two-dimensional S-CONPRI
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+3D B-FEAT
+solid I-FEAT
+elements E-FEAT
+so O
+as S-MATE
+to O
+reduce O
+the O
+computation S-CONPRI
+cost O
+for O
+shape O
+optimization S-CONPRI
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+
+
+To O
+decrease O
+the O
+threshold O
+of O
+customization O
+of O
+surface B-FEAT
+structure E-FEAT
+for O
+the O
+public O
+when O
+using O
+AM S-MANP
+, O
+in O
+, O
+an O
+interactive O
+CAD S-ENAT
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+tool S-MACEQ
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+proposed O
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+
+
+This O
+tool S-MACEQ
+uses O
+predefined O
+reference O
+unit O
+models O
+with O
+the O
+inputs O
+of O
+user O
+'s O
+stylings O
+to O
+automatically O
+generate O
+customized O
+hollowed O
+surface B-FEAT
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+for O
+fashion S-CONPRI
+. O
+
+
+Similar O
+to O
+other O
+existing O
+3D S-CONPRI
+porous O
+structure B-FEAT
+design E-FEAT
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+tool S-MACEQ
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+mainly O
+based O
+on O
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+tessellation E-FEAT
+and O
+curve O
+fitting O
+methods O
+. O
+
+
+26 O
+shows O
+the O
+surface B-FEAT
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+generation O
+process S-CONPRI
+. O
+
+
+The O
+main O
+advantage O
+of O
+this O
+tool S-MACEQ
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+that O
+its O
+predefined O
+reference O
+models O
+can O
+be S-MATE
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+tested O
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+ensure O
+manufacturability S-CONPRI
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+which O
+will O
+avoid O
+problems O
+during O
+AM S-MANP
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+
+
+Similar O
+to O
+structure S-CONPRI
+topology O
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+design S-FEAT
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+optimization B-CONPRI
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+in O
+the O
+modelling S-ENAT
+, O
+simulation S-ENAT
+and O
+embracing O
+of O
+AM S-MANP
+constraints O
+. O
+
+
+This O
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+work O
+on O
+the O
+data S-CONPRI
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+analysis O
+and O
+optimization S-CONPRI
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+
+A O
+lightweight S-CONPRI
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+convenient O
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+platform S-MACEQ
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+be S-MATE
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+to O
+efficiently O
+acquire O
+the O
+calculation O
+results O
+for O
+valid O
+surface B-FEAT
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+design S-FEAT
+and O
+optimization S-CONPRI
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+
+Currently O
+, O
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+is O
+very O
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+the O
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+structure E-FEAT
+in O
+AM S-MANP
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+
+Most O
+of O
+the O
+design S-FEAT
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+are O
+limited O
+at O
+non-metallic O
+AM B-MANP
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+
+
+However O
+, O
+there O
+is O
+an O
+ugent O
+need O
+in O
+the O
+medical B-APPL
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+where O
+special O
+functional O
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+
+27 O
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+a O
+bio-insipred B-FEAT
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+structure E-FEAT
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+a O
+special O
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+
+Reverse B-CONPRI
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+used O
+to O
+generate O
+the O
+surface B-FEAT
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+
+However O
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+modelling S-ENAT
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+function O
+validation S-CONPRI
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+such O
+surface B-FEAT
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+been O
+studied O
+. O
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+
+Hence O
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+should O
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+support S-APPL
+the O
+medical S-APPL
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+for O
+metal B-MANP
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+. O
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+
+6 O
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+the O
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+the O
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+to O
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+the O
+internal B-FEAT
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+
+In O
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+previous O
+sections O
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+surface S-CONPRI
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+geometry S-CONPRI
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+
+In O
+many O
+cases O
+these O
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+required O
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+ways O
+of O
+defining O
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+
+With O
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+or O
+limited O
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+very O
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+geometric O
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+
+Many O
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+to O
+internal O
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+media O
+through O
+the O
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+
+In O
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+the O
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+
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+blocked O
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+excess O
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+
+Finally O
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+created O
+by O
+ensuring O
+process-induced O
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+
+Here O
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+stable O
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+
+6.1 O
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+the O
+transportation O
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+
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+location O
+and O
+shape O
+of O
+these O
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+
+In O
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+the O
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+have O
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+
+Thomas O
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+7mm O
+could O
+be S-MATE
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+problems O
+. O
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+
+Above O
+that O
+, O
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+overhanging O
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+noticed O
+, O
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+well O
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+, O
+leading O
+to O
+recoater O
+collisions O
+. O
+
+
+Other O
+channel S-APPL
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+have O
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+proposed O
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+
+With O
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+
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+reduce O
+cycle O
+time O
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+
+Kitayama O
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+the O
+effect O
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+
+Results O
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+improvement O
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+% O
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+
+Although O
+conformal B-CONPRI
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+actual O
+application O
+in O
+industry S-APPL
+lags O
+behind O
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+
+It O
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+considered O
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+only O
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+complex O
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+quickly O
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+very O
+high O
+production S-MANP
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+. O
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+
+H O
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+hot B-MANP
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+
+Current O
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+manifold O
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+two O
+main O
+themes O
+; O
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+flow O
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+
+Conventional O
+methods O
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+straight O
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+which O
+influences O
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+Ma O
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+
+AM S-MANP
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+the O
+design S-FEAT
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+smooth O
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+between O
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+up O
+to O
+a O
+factor O
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+3 O
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+
+6.2 O
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+, O
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+minimal O
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+chosen O
+is O
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+factor O
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+
+Thomas O
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+some O
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+these O
+limits S-CONPRI
+, O
+for O
+example O
+as S-MATE
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+in O
+31 O
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+
+
+Printing O
+of O
+free O
+standing O
+walls O
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+pilars O
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+a O
+limiting O
+factor O
+as S-MATE
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+minimal O
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+sectional O
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+maximal O
+aspect B-FEAT
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+limited O
+. O
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+
+In O
+sectors O
+like O
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+, O
+ventilation O
+, O
+and O
+air O
+conditioning O
+, O
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+
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+
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+
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