Seite - 103 - in 3D Printing of Metals

Metals 2016,6, 280 Therearesomeindependentcavitiescreatedbytheinnerframes. Everycavitywasgivenapowder outletof1mmdiameterat theappearanceofparts todischargeredundantpowders. Thefinaldesign model is showninFigure24. Theredzoneshowsthepowderoutletsof theconnectingplate. Figure24.Finaldesignmodelof theconnectingplate. Theweightofanarmoredvehicle is22,500kg. Theredesignedconnectingplatewasassembled in thisvehicle to test itsperformance invariousconditions. The test includesastraightdrive test, apivot turntest, andabrake testat15km/hand30km/h, respectively. Besides, thisvehicle runover30km onagravel road. TheassemblyproceduresareshowninFigure25. Figure 25. The assembly of reduction gear (A), tightening of bolts on connected plate (B), positionadjustmentofconnectedplate (C),finishofconnectedplateassembly(D). 4.ResultsandDiscussion Theresultsof the tensileexperimentsareshowninTable4. Thecylindersampleswere fractured at about 1069.6MPa, weaker than 1340MPa, which is the normal value of the tensile strength of IN718partsmanufactured by casting. Thismaybe because of themicro-segregation of IN718 duringprocessing. Table4.Resultsof tensile tests. Material Process YieldStrength/MPa TensileStrength/MPa Elongation IN718 cast 1100 1340 12% SLM X–Y 780 1069.6 30.9% Z 634 980 - The results of the compression tests are shown in Figure 26. The samples of 0.5 mm and 1.0mmdiameterwerecompressedperpendicularlywhile thesampleof1.5mmoccurredwith lateral 103