Hot Deformation Behavior and Processing Map of a New High-Temperature Titanium Alloy

Isothermal constant strain rate compression testing of a new as-cast high-temperature titanium alloy Ti-6.5Al-11.5(Sn,Zr)-2.5(Mo,W,Nb)-0.25Si-0.1Er was carried out at the deformation temperatures range from 900°C to 1100°C, strain rate range from 0.001 to 1 s-1 and 60% of engineering strain. The deformation behavior of this high-temperature titanium alloy was analyzed based on the stress-strain result, and the constitutive equation based on the hyperbolic sine model and the parameters of Zener–Hollomon was established, showing a close accordance with the experimental value. The hot processing maps based on the dynamic material model and the Prasad’s instability criterion were constructed at strains of 0.3 and 0.6. The maps exhibit two stable deformation domains in the temperature range of 940~960°C and strain rate range of 0.001~0.002s-1, and in the temperature range of 1030~1070°C and strain rate range of 0.02~0.06s-1 with the power dissipation efficiency of 58.5% and 54.5%, respectively.