Detwinning of AZ31 magnesium alloy during in situ tension

The aim of this study is to reveal the three detwinning events in AZ31 Mg alloy during in situ tensile test via electron backscatter diffraction (EBSD). To better understand the detwinning mechanisms, shear displacement gradient tensors were used to evaluate local strain accommodation. The results revealed that the strain concentration was responsible for the detwinning of the pre-existing twin. Also, for the two newly formed twins, the shear displacement gradient tensors of the basal and prismatic slip in the adjacent grains can hinder their growth and eventually lead to the detwinning. Detwinning can occur when grains lack effective deformation modes to accommodate the strain from neighboring grains. The kind of local strain accommodation was affected by twin variants and slip modes on both sides of the grain boundary.