Page - 97 - in 3D Printing of Metals

Metals 2016,6, 280 The comparison between the stress distribution density of the traditional (Figure 14a) and optimized parts (Figure 14c) is shown in Figure 15. As can be seen fromFigure 15, the average stressof theoptimizedstructurebecamelarger. Thus, theefficiencyof thestructurewas improved. Figure15.Stressdistributiondensityof traditionalandoptimizedrings. Togetcomponentswithdifferentperformances, thenumberofstiffenersNandthe thicknessof theframeηweretakenasdesignparameters. Figure16showsthefiniteelementanalysis resultswhich illustrate the influenceof thenumberof stiffenersN and the thicknessof frameηon the structure stress. Theperformanceof thestructure improvedwith these twoparameters. Figure16. Influenceofdesignparametersonthestructural stressof ring. 3.2.4. L-ShapeFramewithBendingMoment TheL-shapestructureoftenbears thebendingmoment. Theoptimizationconditionsaredefined as follows. (1) Objective function:minimumstructuremass (2) Condition1: oneendisfixedandtheotherendisappliedto thevertical load; (3) Condition2: oneendisfixedandtheotherendisappliedto thehorizontal load (4) Boundarycondition: therightboundaryisfixedandthe left surface isappliedtothesurfaceforce (5) Designspace: brownregion ingraph (6) Minimumthickness: 0.006m (7) Designconstraints:meetingthestrengthrequirementswithminimummass 97