Asymmetry strain hardening behavior in Mg-3%Al-1%Zn and Mg-8%Gd-3%Y alloy tubes

The asymmetry strain hardening behavior had been detected during tension and compression for Mg-3%Al-1%Zn (AZ31) and Mg-8%Gd-3%Y (GW83) extruded tubes. In-situ electron backscattered diffraction (in-situ EBSD) was used to analyze the microstructure and texture evolution processes in ambient temperature. The results show that high strain hardening rate in AZ31 compression test was caused by the growth of large fraction extension twinning to cover the whole matrix grain. And the weaker texture, lower volume fraction of twins and multiple dislocation slip in GW83 alloy are responsible for the better yield symmetry and lower strain hardening rate compared with AZ31 alloy tube.