Influence of strain rates on high temperature deformation behaviors and mechanisms of Ti-5Al-5Mo-5V-3Cr-1Zr alloy

Highlights: • Localized deformation become more obvious with the increasing strain rate. • DRV and CDRX play a dominant role in the discontinuous yielding behavior. • CDRX along β grain boundaries and DDRX within β grains occurred under 0.01 s⁻¹. In this work, isothermal compression tests of Ti-5Al-5Mo-5 V-3Cr-1Zr alloy under strain rates from 0.01 s⁻¹ to 1 s⁻¹ at 900 °C was carried out. With the increasing strain rate, the flow stress increased and the thickness of the central deformation band decreased significantly. Compared with the deformation at the strain rate of 0.01 s⁻¹, the discontinuous yielding behavior was observed at 0.1 s⁻¹ and 1 s⁻¹. It was also found that the continuous recrystallization (CDRX) along β grain boundaries and discontinuous dynamic recrystallization (DDRX) within β grains occurred under 0.01 s⁻¹. When the strain rate increased to be 1 s⁻¹, profound residual dislocations in β grains formed, showing typical characteristic of dynamic recovery (DRV) and continuous dynamic recrystallization (CDRX).