A slip-based model for strength evolution during cyclic loading

Motivated by the strong dependence of strain-hardening processes on slip system activity, a slip system hardening formulation that explicitly employs accumulated slip system shear strains and net crystal shearing rates is introduced within a polycrystal plasticity modeling formulation for predicting material response during cyclic deformation. The model, which is a slight modification of the Voce hardening model commonly employed for large, strain forming simulations, was employed to model the behavior of 304L stainless steel subjected to uniaxial and multiaxial nonproportional multiple-step experiments and multiaxial multiple-phase angle experiments. The model successfully captured the pseudosaturation response that is common during the multiple-step tests and captured many of the loop-shape and stress-level features of the multiple-phase angle experiments.