Abstract:The deformation behavior and mechanisms of Ti-1023 alloy were studied in the temperature range of 650−900 ℃ and strain rate range of 0.001−10 s−1 by compression and tensile tests. The results show that in a limited strain rate range of 0.001−0.1 s−1, the kinetic rate equation is obeyed and a linear fit is obtained at all the temperatures. The apparent activation energy is 322 kJ/mol in the α-β region and 160 kJ/mol in the β region, respectively. Power dissipation maps of this alloy developed by using Gleeble test data show three domains in the tested range. Superplasticity, marked by abnormal elongation at 700 ℃, occurs in the temperature range of 650−750 ℃ and at strain rates below about 0.03 s−1. Large grain superplasticity takes place in the temperature range of 750−850 ℃ and strain rates range of 0.001−0.03 s−1. Dynamic recrystallization occurs in the temperature range of 850-900 ℃ and at strain rates below about 1 s−1. The instability maps of this alloy were also developed.

Key words: Ti-1023 alloy; deformation behavior; deformation mechanisms; processing maps; superplasticity