Bài báo khoa học

This paper presents the identification of dislocation-density-based crystal plasticity parameters for a A508 Cl3 bainite steel in non-irradiated and irradiated states and at different temperatures. The representative volume element for the identification process is a cube containing 1000 steel grains represented by a Voronoi mosaic discretized by finite elements. The grains are assigned crystallographic orientations corresponding to an isotropic texture. The crystal constitutive model is based on a plastic flow law, a hardening law, and a law of evolution of dislocation densities. Modeling parameters are determined by a two-step calculation with two different crystal structures: (1) using a simple structure with 343 identical grains to identify 7 parameters, (2) using a Voronoi tessellation of 1000 grains to refine the parameters. Thereafter, the calculated stress-strain curves are compared with experimental stress-strain curves. The results show that the simulated stress-strain curves are in good agreement with those of experiments, highlighting the reliability of the proposed procedure to account for the significant effects of irradiation and temperature