Deformation characteristics of IMI685 titanium alloy under β isothermal forging solutions

The deformation behaviour of IMI685 titanium alloy during isothermal forging in the β phase field has been studied in the temperature range 1025 to 1070 °C, and at the strain rate range of 0.09 to 0.005 s−1. The true stress-true strain curves obtained within the regime explored are typical of dynamic recovery, and the metallography of the pressed samples also revealed that no dynamic recrystallization occurred during the forging. Two methods were used for the correlation of the experimental data. First, when the experimental data were fitted to the power law equation, the activation energy for β forging of IMI685 was calculated as Q = 193 kJ mol−1. Second, with the consideration of the dependence of strain rate sensitivity on strain rate, an empirical equation was obtained, which provided a better correlation than the power law equation.