Loading Mode Dependence of Twin‐Twin Boundary Formation in a Textured Magnesium Alloy

ABSTRACT Twin‐twin boundaries play vital roles in microstructure evolution and tailoring mechanical properties. In this work, the atomic structures of twin‐twin boundaries formed by interactions between tensile twin variants sharing the same or different zone axes in a deformed magnesium alloy are investigated. Strain accumulation induced by twin‐twin interactions causes the lattice distortion around the intersecting area, which promotes the formation of twin‐twin interfaces. The characteristics of twin‐twin boundaries significantly depend on the activation of twin variants involved in the interactions. The lattice distortion around the twin‐twin boundary region can contribute to the subdivision of coarse grains and suspension of twinning propagation, as well as the absorption of dislocations and nucleation of new grains in the subsequent thermomechanical process.