Abstract:Dynamic recrystallization (DRX) behavior in β phase region for the burn resistant titanium alloy Ti-25V-15Cr-0.2Si was investigated with a compression test in the temperature range of 950-1100 °C and the strain rate of 0.001-1 s^-1. The results show that deformation mechanism of this alloy in hot deformation is dominated by DRX, and new grains of DRX are evolved by bulging nucleation mechanism as a predominant mechanism. DRX occurs more easily with the decrease of strain rate and the increase of deformation temperature. Grain refinement is achieved due to DRX during the hot deformation at strain rate range of 0.01-0.1 s^-1 and temperature range of 950-1050 °C. DRX grain coarsening is observed for the alloy deformed at the higher temperatures of 1100 °C and the lower strain rates of 0.001 s^-1. Finally, in order to determine the recrystallized fraction and DRX grain size under different deformation conditions, the prediction models of recrystallization kinetics and recrystallized grain sizes were established.

Key words: burn resistant titanium alloy; deformed microstructure; deformation mechanism; dynamic recrystallization prediction models