Structural characterization of 101¯2 irregular-shaped twinning boundary in hexagonal close-packed metals

In deformation twinning, the twinning boundary (TB) contour usually looks elliptical. Here, the 101¯2 TB contours are investigated in AZ31, Ti and Co by using transmission electron microscopy (TEM) and high-resolution TEM, suggesting a very irregular shape. The formation of a 101¯2 irregular-shaped TB is closely related to the interface defects and basal-prismatic interfaces, which place basal and prismatic planes face to face.