Stress state-dependent mechanics of additively manufactured 304L stainless steel: Part 2-Characterization and modeling of macroscopic plasticity behavior

A model that describes macroscopic plasticity behavior of additively manufactured 304L stainless steel, in terms of its stress state-dependent microstructural austenite-to-alpha' martensite phase transformation is developed. Specifically, a stress state-, texture-, and chemistry-dependent strain-induced martensitic transformation kinetics equation was coupled to an isotropic hardening law in order to explicitly link the macroscopic strain hardening behavior in this material to its microstructural evolution. The plasticity model was implemented into a finite element code, calibrated using experimental data under uniaxial tension, uniaxial compression, pure shear, and validated using experimental data under combined tension and shear loading. The simulated results were in good agreement with the corresponding experimental data for all stress states studied for calibration and validation, demonstrating the predictiveness of the plasticity model developed.