A twin size effect on thermally activated twin boundary migration in a Mg-3Al-1Zn alloy

A strong twin size effect on thermally activated twin boundary migration in a Mg-3Al-1Zn alloy (AZ31) is reported. The narrow twin lamellae tend to be consumed by the large neighboring matrix during annealing at high temperature. However, when the twin lamellae are much larger than the matrix, the twins prefer to consume the matrix. The consumption of twins by matrix leads to a transformation of the twin orientation into the matrix orientation and vice versa.