A texture-based representative volume element crystal plasticity model for predicting Bauschinger effect during cyclic loading

Abstract

A texture-based representative volume element (TBRVE) crystal plasticity model is developed to predict the Bauschinger effect (BE) in rolled polycrystalline aluminium alloy 7075 under cyclic loading. The TBRVE is systematically created using the Voronoi tessellation method and discretisation of orientation distribution function, to more accurately represent both the grain morphology and crystallographic texture. Simulations of loading in the transverse and rolling directions are conducted using a backstress incorporated crystal elasto-viscoplastic model. The hysteresis loops are successfully predicted by the proposed model up to saturation, and the BEs in both the transverse and rolling directions are also captured. For the first time, the effects of backstress and residual stress, which induce the mechanical BE and microstructural BE respectively, are quantitatively determined through simulation. It is found that they have similar contributions to the total BE. This study indicates that TBRVE is important for crystal plasticity finite element method to effectively reproduce the anisotropy of the material, and more importantly, determine the components of BE during cyclic loading.