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 alpha grains of Ti-5Al-2Sn-2Zr-4Mo-4Cr alloy is accomplished by the formation of high-angle boundaries (HABs) and the penetration of the beta phase during isothermal compression, and an increase in deformation temperature leads to a more globular microstructure. The main restoration mechanism in the beta 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 alpha grains play an important role in recrystallization. The recrystallization in the beta 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 < 001 > 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. (C) 2014 Elsevier B.V. All rights reserved.