A pseudoelastic model for deformation twinning: Numerical homogenisation and comparison to experiments

Abstract

A pseudoelastic micromodel that accounts for deformation twinning and crystallographic slip (Gl¨uge

et al., 2010) is used in conjunction with the representative volume element (RVE) method. The material model consists basically of a nonconvex visco-elastic stress strain-relation, and has to be considered as a microscale-model. The material parameters are adopted to {10¯12}<-1011> twinning in magnesium. The simulation setup follows the commonly conducted compression tests on extruded Magnesium rods, where due to twinning a strong change of texture and a strength differential effect can be observed. The simulations allow for an investigation of the twin propagation in the polycrystal. Furthermore, the simulated twin volume fraction evolution, the texture evolution and the macroscopic stress-strain relation could be compared to experimental findings obtained with pure magnesium and the magnesium based alloy AM30.