A CPFEM-Based Virtual Testing Approach for Characterizing Anisotropic Plastic Behavior of Additively Manufactured Low-Carbon Lath Martensitic Steel

Additively manufactured low-carbon lath martensitic steel can exhibit direction-dependent mechanical behavior due to process-induced microstructural heterogeneity. However, direct experimental characterization of the corresponding anisotropic constitutive response remains challenging. In this study, a microstructure-informed representative volume element (RVE) and crystal plasticity finite element modeling (CPFEM) are employed to perform virtual mechanical tests and to examine the macroscopic anisotropic plastic response. Based on the CPFEM results, a continuum-level constitutive description is constructed for use in engineering-scale simulations where experimental data are limited. The predicted constitutive response is then compared with experimental observations, showing reasonable agreement in the measured directional behavior. The results suggest that RVE-based CPFEM can provide a useful basis for identifying anisotropic constitutive behavior and for supporting continuum-scale modeling of additively manufactured steels.