Constitutive equation to predict elevated temperature flow stress of V150 grade oil casing steel

► The hot deformation behavior of V150 grade oil casing steel was investigated. ► The material shows strain hardening, strain rate hardening and thermal softening. ► Constitutive equation was improved by incorporating the effect of the strain. ► R = 0.994 and AARE = 4.21% revealed satisfactory prediction for the entire domain.