Investigation on hot deformation mechanism of Ti-17 alloy

The high temperature deformation characteristic of Ti-17 alloy was investigated using hot compressive test. Through metallographic and TEM observation, it was found that in β region the dominant deformation mechanism is dynamic recovery characteristic of diffusion, at high strain rate, only dynamic recovery operated, while at low strain rate, continuous recrystallization takes place. In (α+β) region, the interface slip is dominant deformation mechanism which results in dynamic recrystallization at high strain rate. The apparent deformation activation energy Q and strain rate sensitivity m were also determined, which are 161kJ/mol and 437kJ/mol, 0.32 and 0.25 in β and (α+β) region respectively.