Determination of Critical Dynamic Recrystallization Conditions and Mechanism Analysis of Ti600 High-Temperature Titanium Alloy

摘要

The dynamic recrystallization behavior of a high-temperature titanium alloy Ti600 has been investigated by hot compression tests at the strain rates of 0.001-10 s(-1) and temperatures of 950-1010 degrees C. The grain boundary migration during deformation has been analyzed, and a critical DRX dislocation density associated with material essence and grain boundary mobility has been proposed to identify the main softening mechanism of Ti600. Additionally, JMAK model has been employed to describe the dynamic recrystallization behavior, which is essential to concerned dynamic recrystallization with material and deformation parameters to investigate the dynamic recrystallization behavior of Ti600. The activation energy Q(SRX) has been calculated as 91.18 kJ. Finally, processing map has been established, and the optimal process window has been present. And EBSD experiments at different temperatures and strain rates have been conducted to deeply study the grain boundary distribution and crystal orientation.