Phenomenological Arrhenius type constitutive equation for a 304 stainless steel during hot deformation

The present study aimed to present a phenomenological and empirically-based constitutive model to predict the flow behavior of 304 stainless steel. hot compression tests were performed at temperatures of 950-1100 °c and strain rates of 0.005-0.5 s−1 up to the strain of 1. to demonstrate flow curves, three regimes were considered including the linear trend up to yield stress, the work hardening-recovery dominant region based on estrin and mecking model from the yield point up to the saturation stress, and the recovery-recrystallization zone from the critical stress extends toward the steady state stress. the avrami-type equation was supposed for the kinetics of recrystallization and validated by the evolved microstructures at strain 1. eventually, the six equations that describe the model via strain, strain rate, and temperature were presented. they have included the arrhenius type equation for the yield, saturation, and steady-state stresses, in addition to the critical strains and the inflection strains together with the relationship for the exponent of avrami-type recrystallization kinetics formula, all as functions of zener-hollomon parameter. comparing the flow curves predicted by the model with the experimental results showed satisfactory coincidence, confirming that the proposed model can give an almost accurate estimation of the flow stresses of 304 stainless steel at different conditions.