Crystal plasticity analysis of plane strain deformation behavior and texture evolution for pure magnesium

A viscoplastic self-consistent model is implemented to study the plane strain deformation behavior and texture evolution of pure magnesium single crystals and polycrystals. The numerical simulations of single crystals are carried out based on seven channel-die compression tests. Due to the different deformation mechanisms of tensile twinning and compressive twinning, the hardenings caused by the twins are distinguished to better describe their effects on the whole deformation. The uniform parameters are calibrated with the channel-die experimental data in single crystal cases and then used to predict the polycrystalline deformation. The polycrystalline aggregates with 100 and 300 random orientations are developed for their plastic deformation. Five various self-consistent schemes are employed to investigate the influence of their linear hypotheses on stress–strain responses. A trend of hardening rate from weak to intense is shown for the five self-consistent schemes: Tangent, n^eff = 10, Affine, Secant and Taylor. The same trend is also obtained in their corresponding texture evolutions and yield surfaces. At low plastic strains, a high asymmetry and a strong anisotropy between compressive and tensile yield strengths are exhibited by the yield surfaces.