Effects of the grain shape and crystallographic texture on the grain-scale mechanical behavior of additively manufactured aluminum alloys

Abstract

The grain shape and texture effects in aluminum alloys manufactured by selective laser melting are studied numerically in terms of micromechanical simulations. The method of step-by-step packing is adopted to generate the three-dimensional grain morphology typical for these materials. Crystal plasticity finite element simulations of uniaxial tension are performed for two models with random and cube-textured columnar grains inherent in selective laser melting. Comparative analysis of the computational results shows a substantial difference between the microscale stress and strain fields. The presence of cube-textured columnar grains provides more homogeneous stress-strain distributions inside the melt pools and unloads the adjacent regions of fine equiaxed grains, thus reducing high stress concentration in them.