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1、TOPOLOGYOPTIMIZATIONFORADDITIVEMANUFACTURINGD.Brackett,I.Ashcroft,R.HagueWolfsonSchoolofMechanicalandManufacturingEngineering,LoughboroughUniversity,Loughborough,Leicestershire,LE113TU,UKAbstractThispapergivesanoverviewoftheissuesandopportunitiesfortheapplicationoft
2、opologyoptimizationmethodsforadditivemanufacturing(AM).Themainanalysisissuesdiscussedare:howtoachievethemaximumgeometricresolutiontoallowthefinefeatureseasilymanufacturablebyAMtoberepresentedintheoptimizationmodel;themanufacturingconstraintstobeconsidered,andthework
3、flowmodificationsrequiredtohandlethegeometriccomplexityinthepostoptimizationstages.Themainmanufacturingissuesdiscussedarethepotentialforrealizingintermediatedensityregions,inthecaseofthesolidisotropicmaterialwithpenalization(SIMP)approach,theuseofsmallscalelatticest
4、ructures,theuseofmultiplematerialAMprocesses,andanapproachtoincludingsupportstructurerequirementasamanufacturingconstraint.IntroductionTopologyoptimizationmethodssolveamaterialdistributionproblemtogenerateanoptimaltopology.Itisusualforeachfiniteelementwithinthedesig
5、ndomaintobedefinedasadesignvariable,allowingavariationindensity(homogenization,SIMP)[1-4]orvoid-solid(bi-directionalevolutionarystructuraloptimization(BESO))[5-9].Othermethodsexistsuchasgeneticalgorithmsandlevelsetmethodsbutthesearestillintheirinfancywithregardstoth
6、eirsuitabilitytoreallifeproblemsandsoarenotdiscussedhere.Usually,topologyoptimizationmethodsareusedtotacklepracticaldesignproblemswithtraditionalmanufacturingprocessesinmind,suchascastingandmachining.Processeswherethepartisproducedbymaterialremovalcanbedescribedassu
7、btractiveprocessesandprocesseswherethepartisproducedbyamoldcanbedescribedasformativeprocesses.Theseapproacheshavesignificantmanufacturingconstraintsthatmustbetakenintoaccountduringthedesignstagetoensureafeasibledesign.Forexample,theneedfortoolaccessinthecaseofmachin
8、ingortheneedforpartremovalfromamoldinthecaseofcastingormolding.Theseconstraintslimitthephysicalrealizationoftheoptimaltopologyandacompromi