Microstructural and Crystallographic Aspects of Yield Surface Evolution

Abstract

The microstructural and crystallographic aspects, reflected at the macroscopic scale on yield surface and its subsequent evolution, are reappraised by application of crystal plasticity simulations. Strain hardening rule in the slip system is coupled to cope with latent hardening and Bauschinger effect. Uniaxial tension simulation on an isotropic polycrystalline aggregate leads to anisotropic strain hardening. Typical elements of phenomenological plastic anisotropy and hardening rules such as expansion, kinematic shift and distortion of the yield surface, are shown to be featured in crystal plasticity by tuning the slip system hardening rules appropriately.

Crystal Plasticity Predictions of Forward-Reverse Simple Shear Flow Stress

“…In order to replace the CRSS hardening slope ∂ τ i /∂Γ mentioned earlier, with Equation 2, the derivative of the hardening curve is obtained as shown in Equation 3 The hardening matrix in this study consists of three kinds of components, each of which represents relative rates of self-, latent-and Bauschinger hardening [1]. These components are denoted as H S , H L and H B , respectively.…”

“…The last characteristic is referred to as permanent softening in which the flow stress does not fully recover that of monotonic loading. These complex behaviors are tackled with a coupled slip system hardening rule suggested in [1]. Simulations and experiments are carried out on a bakehardenable (BH) steel sheet sample.…”