Stress relaxation induced morphological evolution and texture weakening of α phase in Ti-6Al-4V alloy

A uniform, fine-grained microstructure is attained by stress relaxation (SRT) method in Ti-6Al-4V alloy subsequent to hot compression (HC) executed at the temperature of 900 °C and a strain rate of 10⁻³ s⁻¹ to a 50% height reduction. The pronounced SRT-induced α grain spheroidization and texture weakening is proposed. It is found that the spheroidization of the initial coarse forging state microstructure is obvious, and texture has weakened substantially after HC/SRT. In addition, the crystal structure of α phase is closer to the ideal crystal structure of α-Ti after SRT. The HC/SRT process is mainly governed by continuous dynamic recrystallization and dynamic/static spheroidization.