Analysis of crystallographic twinning and slip in fcc crystals under plane strain compression

Abstract

The Bishop–Hill maximum work principle was applied to analyze the contribution of {1 1 1}〈1 1 0〉 slip and {1 1 1}〈1 1 2〉 twinning to the deformation of face-centered cubic crystals under plane strain compression. The influence of ξ, the ratio of critical resolved shear stress for twinning to that for slip, on the yield stress states and the selection of active systems for main ideal orientations of interest was investigated. The results showed that twinning is difficult for the {1 0 0}〈0 0 1〉, {1 1 0}〈0 0 1〉 and {1 1 2}〈1 1 0〉 orientations, and becomes easier for the {1 1 0}〈1 1 2〉, {1 1 2}〈1 1 1〉, {1 2 3}〈6 3 4〉, {1 1 0}〈1 1 1〉 and {1 1 0}〈1 1 0〉 orientations. Compared with pure slip, the yield strength anisotropy decreases with the introduction of twinning. A factor based on the Taylor factors was introduced to describe the twinning ability of different orientations. The analytical results are in qualitative agreement with the experimental rolling textures in a Cu5%Zn alloy. The effect of the ξ on the rolling texture development at the polycrystalline level was also illustrated by simulations using the full constraints Taylor model.