Nonlinear multivariate constitutive equations for modeling hot deformation behavior

Abstract Nonlinear constitutive equations are proposed to model variations in flow stress as a function of strain rate and temperature during hot deformation. Modified applied seventy data sets about deformation alloys. Two modifications conventional models introduced, viz. (1) nonlinear (2) multivariate with the fitting simultaneously two variables. The predictive accuracy was evaluated using three statistical parameters compared Arrhenius-like model. It is shown that have improved for advantages include less computation material constants independent or rate. In another type model, expressed linear polynomial functions Zener-Holloman parameter. This approach gives single value activation energy results indicated generalized second-order equation can be used better predict stress, temperature,