Physics-based Constitutive Model for the Hot Deformation of 2Cr11Mo1VNbN Martensitic Stainless Steel

The hot deformation behavior of 2Cr11Mo1VNbN martensitic stainless steel is investigated through isothermal compression tests between 1173 and 1423 K with strain rates of 0.005-5 s−1. Based on experimental results, the work hardening–dynamic recovery stage and dynamic softening stage are evaluated, and a couple-stage constitutive model is developed to describe the work hardening–dynamic recovery and dynamic softening behaviors. Phenomenological constitutive models, which consider temperature, strain and strain rate, are established. A comparison between the predicted and experimental flow stress values indicates that the established models accurately describe the hot deformation behaviors for the studied supercritical steel.