Biaxial Ratcheting Analysis based on Real Behaviors of Subsequent Yield Surface

Abstract To develop a plastic constitutive equation for general plastic deformation analysis, it is useful to confirm that the constitutive equation is viable for analyzing mechanical ratcheting in which a small strain accumulates along with cyclic loading. Many constitutive models and analyses on mechanical ratcheting have been proposed. However, most models do not consider distortion and rotation of the subsequent yield surface observed in the process of ratcheting deformations. In this study, behaviors of both the subsequent yield surface and the ratcheting deformations have been experimentally evaluated for the initially isotropic metals of SUS316FR stainless steel, 6-4 brass and S25C mild steel, which were subjected to biaxial mechanical ratcheting. Simulation analysis of biaxial ratcheting was conducted based on real behaviors of the subsequent yield surfaces such as swing rotation, translation, and distortion observed in ratcheting, and the two-surface hardening rule. The reliability of the proposed plastic constitutive model was verified by comparing the numerical results with the corresponding experimental results.