Evolution of coordination between α and β phases for two-phase titanium alloy during hot working

The evolution of coordination between α and β phases for a two-phase titanium alloy was investigated. For this purpose, hot compression and heat treatment under different conditions were carried out. The results show that the ability of coordinated deformation between α and β phases can influence uniformity of microstructure evolution. Specifically, α phase maintains the lamellar structure and β phase has a low degree of recrystallization when the ability of coordinated deformation is good. In this case, α and β phases still maintain the BOR (Burgers orientation relationship), and their interface relationship is not destroyed even at large deformation. Both of the deformation extent of α lamellae and recrystallization degree of β phase increase with the decline of ability of coordinated deformation. The α phase only maintains the BOR with β phase on one side, while the uncoordinated rotation with the β phase on the other side occurs within 10°. The α and β phases rotate asynchronously when ability of coordinated deformation is poor. The degree of interface dislocation increases, and α and β phases deviate from the BOR.