Large strain shear and torsion of rate-sensitive FCC polycrystals

Abstract

The behaviour of FCC polycrystals subjected to large strain uniform simple shear is first investigated. A rate-sensitive polycrystal model is used to compute to compute the resulting axial and shear stresses on the polycrystal, and to simulate the texture evolution. Both “full constraint” and “relaxed constraint” versions of this model are considered. A rigorous analysis is then carried out to extend the simple shear results to the case of axially-constrained solid circular bars in torsion, where it is assumed that the solid bar has the same polycrystalline properties as the element analysed for simple shear. It is shown that the predicted trends for solid bar torsion can differ significantly from those for uniform simple shear. The simulated textures obtained with the full constraint polycrystal model are seen to be in better agreement with experimental textures for copper than those predicted by the relaxed constraint model.