Modeling of additively manufactured materials using gradient-enhanced crystal plasticity

Additively manufactured metals possess a particular grain structure – ranging from equiaxed grains to columnar grains – which is strongly influenced by the manufacturing process. The grain structure determines the material behavior and therefore influences the mechanical behavior of additively manufactured parts. In the present contribution a mesoscopic model, based on gradient-enhanced crystal plasticity, is developed and used to simulate the behavior of additively manufactured Inconel 718. The gradient-enhanced crystal plasticity model is extended to account for relative misorientations of the grain boundaries. Representative Volume Elements of the material are generated using a Voronoi tessellation based method. Computational homogenization is used to identify the macroscopic elastic and plastic mechanical behavior, such as the anisotropic Young’s moduli and the yield locus diagram. The numerical results are validated against experimental data