Effect of temperature on grain growth kinetics of high strength Ti–2Al–9.2Mo–2Fe alloy

Grain growth behaviors of a beta titanium alloy (Ti–2Al–9.2Mo–2Fe) have been systematically investigated for various temperatures. Quantitative evaluations of the grain growth kinetics over a wide range of temperatures from 820 °C to 1000 °C have been performed. The results showed that the isothermal grain growth kinetics followed the normal growth behavior. The solution-treated alloy at lower temperatures (820–900 °C) exhibited a good uniformity of the grain size. It showed a poor uniformity of the grain size due to the abnormal grain growth at higher temperatures (950–1000 °C). The grain growth exponent values ( n ) were at the range of 0.1–0.2, about 0.1 at lower temperatures and about 0.2 at higher temperatures. They were lower than other beta titanium alloys. The lower exponent values ( n ) and the higher activation energy ( Q ) can be attributed to the solute drag effect and the high Mo content with low diffusivity in Ti matrix.