Mechanical responses and deformation mechanisms of an AZ31 Mg alloy sheet under dynamic and simple shear deformations

Abstract

The mechanical responses and deformation mechanisms of AZ31 Mg alloy sheets were studied under dynamic (tension and compression) and simple shear deformations along different in-plane loading directions. This paper is a continuation of the author’s previous manuscript (Khan et al., 2011) on the quasi-static responses and texture evolution of AZ31 Mg alloy sheets. The strain-hardening rate (dσ/dε) of specimens under in-plane dynamic compression at room temperature showed a strong strain-rate dependency when deformation entered the dynamic region. The electron back-scattered diffraction (EBSD) technique was used to conduct texture analysis on each specimen after simple shear deformation under a quasi-static load (100s−1) at 150°C and after dynamic compression under a strain rate of 1500s−1 at RT and 150°C. Loading direction during simple shear deformation did not significantly affect either the texture evolution or the twinning evolution. Deformation temperature during dynamic compression affected both the texture evolution and the twinning evolution only slightly, but it significantly affected the kernel average misorientation (KAM) distribution in deformed grains. A visco-plastic self-consistent (VPSC) polycrystal model was successfully used to simulate the mechanical responses and the evolution of the initial texture in an AZ31 Mg alloy sheet during simple shear deformation and dynamic compression.