Influence of {10(1)over-bar2} twin characteristics on detwinning in Mg-3Al-1Zn alloy

In the present work, the influence of pre-induced (10 (1) over bar2) twin characteristics on detwinning activation in a basal texture magnesium alloy is systematically investigated by a combination of electron backscatter diffraction technique and mechanical tests. Samples containing pre-induced (10 (1) over bar2) twin variants with different morphological characteristics are prepared by pre-strain path change tests comprised two pre-strain paths: (i) compression along the rolling direction of magnesium alloy plate; (ii) tension along the normal direction of magnesium alloy plate. In the former case, a single (10 (1) over bar2) twin variant or a (10 (1) over bar2) twin pair is formed in one grain. While, multiple (10 (1) over bar2) twin variants are usually activated simultaneously in one grain in the latter case. During subsequent compression along normal direction, detwinning process is effectively retarded for the samples containing multiple (10 (1) over bar2) twin variants in one grain. Meanwhile, the yield stress of corresponding samples is enhanced as well, compared to that of the samples containing a single (10 (1) over bar2) twin variant or a (10 (1) over bar2) twin pair in one grain. According to these experimental features, the possible reasons behind such phenomena are proposed and discussed.