Characterization of ductile damage and fracture behavior under shear reverse loading conditions

Abstract

This paper deals with experimental and numerical analysis of the ductile damage and fracture behavior undergoing biaxial non‐proportional shear reverse loading conditions. In the numerical analysis, an anisotropic cyclic plastic‐damage constitutive model is considered to characterize the damage and fracture behavior. Additionally, the change in the hardening rate is observed after shear reverse loading. Thus, a newly modified non‐hardening strain region method is introduced to capture the change in the hardening ratio between isotropic and kinematic hardening. Furthermore, the damage surface is assumed to translate in the direction of the damage strain increment. Hence, a softening law based on the damage strain is proposed. The modified constitutive model predicts macroscopic force‐displacement and microscopic evolution of plastic and damage behaviors under shear reverse loading with a tensile preload. Through digital image correlation technique and scanning electron microscopy, numerical results can be validated by experimental ones. Furthermore, scanning electron microscopy pictures also reveal different damage and fracture mechanisms on the micro‐level.