Development of Constitutive Relationship for the Hot Deformation of Ti-47Al-2Cr-2Nb-0.2W Alloy
The high temperature deformation behaviors of Ti-47Al-2Cr-2Nb-0.2W alloy were investigated by isothermal compressive tests, performed at temperatures between 1000 and 1150 , strain rates between 0.001s-1 and 1s-1. The stress-strain curves of IM alloy exhibited an obvious work hardening peak followed by a broad flow softening at high strain rates(≥0.1s-1) while work hardening could hardly be seen from the stress-strain curves at low strain rates(≤0.01s-1). Also, the constitutive equation of the alloy had been established to describe the flow behavior. The apparent activation energy of hot deformation was calculated to be 351.61kJ/mol. The size of the recrystallized grain increased with increasing temperature and with decreasing strain rate, namely with decreasing the Zener-Hollomon parameter Z. It is necessary to select proper Z, that is, to strictly control the deformation parameters in order to obtain a homogeneous and fine microstructure.
Jingtao Han, Zhengyi Jiang and Sihai Jiao
H. Wang et al., "Development of Constitutive Relationship for the Hot Deformation of Ti-47Al-2Cr-2Nb-0.2W Alloy", Advanced Materials Research, Vols. 156-157, pp. 625-632, 2011