Study of reversible motion of [formula omitted] tensile twin boundaries in a magnesium alloy during strain path changes

Abstract

Twinning process involving reversible motion of twin boundaries was examined and quantified in a rolled Mg-3Al-1Zn magnesium alloy compressed along two perpendicular directions. The evolution of twinning is analyzed by quasi in-situ electron backscatter diffraction technique, and the detailed structure of the twin boundary is analyzed using high-resolution transmission electron microscopy technique. The results suggest that both twinning and detwinning are attributed to the mobility of twin boundaries. Low-angle boundaries were identified at the prior twin boundaries after detwinning due to the effect of alloying elements, and these low-angle boundaries will affect subsequent deformation. Twin boundary is serrated and consists of 101¯2 coherent twin boundaries and prism-basal boundaries that control twin boundary migration.