Origin of {332} <113> twinning and twin-twin intersections in a shock load metastable Ti-12Mo alloy

In this study, the origin of {332} < 113 > twinning and twin-twin intersections in a shock load metastable beta Ti-12Mo alloy were investigated. Direct observation of partially retained a '' phase and a '' {130} < 310 > twins in the junction areas of intersecting {332} < 113 > twins revealed the {332} < 113 > twinning mechanism to be beta -> alpha '' -> alpha T-{130}'' -> beta({332}T), filling the gap in understanding the stress induced alpha '' phase and alpha '' twinning behavior. Three types of twin-twin intersections were observed, including retaining alpha '' phase, secondary {332} < 113 > twinning and formation of kink bands in the intersecting areas.