Quantitative Analysis on Contribution of Extension Twinning to Plastic Deformation of Mg Alloy by in-situ Tracking on Grains Orientation

The orientation evolution of Mg alloy grains was in-situ tracked during compression at 100 °C by the method of electron backscatter diffraction, and meanwhile, quantitative analysis was also conducted on activations of slips and twinning. Effects of extension twinning activation on slips activations were analyzed during deformation based on calculation of variations of Schmid factor for different slips before and after twinning. It is predicted that there are not distinct changes for Schmid factor of basal slips before and after twinning for Mg alloy grains with basal textured orientation, while the Schmid factor of prismatic slips decreases distinctly after twinning and accordingly they are hard to be activated during the subsequent deformation. Simultaneously, the Schmid factor of pyramidal slips increases distinctly after twinning and it is relatively easy for them to be activated during the subsequent deformation.