Dynamic globularization and restoration mechanism of Ti-5Al-2Sn-2Zr-4Mo-4Cr alloy during isothermal compression

Dynamic globularization and restoration mechanism of Ti-5Al-2Sn-2Zr-4Mo-4Cr alloy during isothermal compression were investigated by employing a high-resolution electron backscatter diffraction technique (EBSD). Quantitative analysis was made in detail for further understanding the microstructure evolution. The results reveal that the dynamic globularization of primary α grains of Ti-5Al-2Sn-2Zr-4Mo-4Cr alloy is accomplished by the formation of high-angle boundaries (HABs) and the penetration of the β phase during isothermal compression, and an increase in deformation temperature leads to a more globular microstructure. The main restoration mechanism in the β phase of Ti-5Al-2Sn-2Zr-4Mo-4Cr alloy during isothermal compression is dynamic recovery (DRC) at a strain rate of 0.01 s^-1, while continuous dynamic recrystallization (CDRX) occurs as the strain rate increases to 1.0 s^-1/5.0 s^-1 and the α grains play an important role in recrystallization. The recrystallization in the β phase of Ti-5Al-2Sn-2Zr-4Mo-4Cr alloy during isothermal compression is promoted with the decreasing of deformation temperature and the increasing of strain rate. A strong 〈0 0 1〉 fiber texture develops where only DRC occurs and the deformation texture is weakened to a large extent after recrystallization of Ti-5Al-2Sn-2Zr-4Mo-4Cr alloy during isothermal compression.