Constitutive relationship for high temperature deformation of powder metallurgy Ti–47Al–2Cr–2Nb–0.2W alloy

The high temperature compressive deformation behavior of powder metallurgy (P/M) Ti–47Al–2Cr–2Nb–0.2 W alloy was investigated at temperatures ranging from 1323 K to 1473 K, and strain rates from 0.005 s−1 to 1 s−1. The flow curves after corrections of the friction and the temperature compensations were employed to develop constitutive equations. The effects of the temperature and the strain rate on deformation behaviors were represented by Zener–Hollomon parameter in an exponent type equation. The influence of strain was incorporated in the constitutive analysis by considering the effect of the strain on material constants. A five-order polynomial was found suitable to represent the influence of the strain. The constitutive equation considering the compensation of the strain predicts very well the flow behaviors throughout the deformation conditions except at 1323 K and 0.005 s−1.

► The flow curves after corrections were employed to develop constitutive equations.
► A five-order polynomial was found suitable to represent the influence of strain.
► The influence of strain was incorporated in the constitutive equation.