Modelization and comparison of Norton-Hoff and Arrhenius constitutive laws to predict hot tensile behavior of Ti–6Al–4V alloy

In order to study the workability of Ti–6Al–4V alloy in the hot forming process for sheets and profiles, the stress-strain experimental data from isothermal hot tensile tests of flat specimens, in the temperature range of 923-1023 K and strain rate range of 0.0005-0.05 s−1 were used to develop the constitutive equation. Arrhenius and Norton-Hoff constitutive models were proposed to characterize the tensile behavior. The fitting results suggest that both Arrhenius constitutive equation (material constants consider the compensation of strain) and modified Norton-Hoff one can predict flow stress of Ti–6Al–4V alloy under most experimental conditions. Further, the modified Norton-Hoff model is more accurate and precise than Arrhenius model.