Seite - 91 - in 3D Printing of Metals

Metals 2016,6, 280 Figure3.Largecurlingofdirectmanufacturingcandidate (a), small curlingofsample fabricatedwith additional skinafterwire-electrodecutting(b) andsample fabricatedwithadditional skin (c). The diameters of the cylinders are 0.5mm, 1.0mm, 1.5mm, 2.0mm, 2.5mm, respectively, asshowninFigure4. ThecompressiontestswereperformedintheMTSInsight30compressiontesting machine (MTS,Minneapolis,MN,USA)at roomtemperaturewitha loadingspeedof0.05mms−1. The control strategy isPosn. The sampleswere tested ina constant loading speed in this strategy. Themaximumloadof thismachine is30KNwitha loadingaccuracyof±5%.Thisexperimentwasby recordedbyacamera tohelp tostudythe trendsofyieldprocessofdifferentstructuresizes. Figure4.Compressiontest sampleswithdifferentparameters. 3. LightweightPartsRedesignMethod Thismethoddisassembledpartsby its shapeand force conditionandreconstructed the inner structureofeachdividedonebycorrespondingthe frameworkstructurewhichwasoptimizedbythe finiteelementmethod,andthenmixedthemtogetherwiththemainframework.Optimizedfoundation frameworkscanbereservedtobuild the framework library,whichcangreatlyshorten thedesigntime usingthismethod. Thebasicflowof thisapproach isshowninFigure5. Figure5.Flowchartof lightweight redesignmethod. 91