Secondary twin variant selection in Mg alloy after a strain-path change

Abstract

Secondary extension twins form in primary extension twins in a deformed Mg alloy after a strain-path change. Statistical analysis reveals that 12.7% of the secondary extension twins correspond to low Schmid factor (SF) twin variants. It is found that these low SF secondary extension twins require the largest or the second largest easy accommodation (i.e., basal slip, prismatic slip or extension twinning) in their neighboring crystals, which could be their host grains, neighboring grains and primary extension twins. Both SF and strain accommodation should be considered to better predict secondary twin variant selection after a strain-path change.