Constitutive Modelling of a New High-Strength Low-Alloy Steel Using Modified Zerilli-Armstrong and Arrhenius Model

Isothermal hot compressive deformation tests were performed on a new high-strength low-alloy (HSLA) steel designated as Steel A over a range of temperatures (950-1100 degrees C) and constant strain rates (0.0003-1 s(-1)). Using the hot deformation flow behaviour data, material constants to establish constitutive relations using revised Zerilli-Armstrong and phenomenological strain-included Arrhenius model were identified. The potential of the established constitutive equations to describe the high-temperature flow behaviour of the material was then compared with standard statistical parameters such as correlation coefficient (R) and average absolute relative error (AARE). The Arrhenius constitutive model proposed by Sellars and Tegart was found to describe the high-temperature flow behaviour of Steel A quite accurately, and hence, this model can be used in simulations of complicated metal-forming processes. The results obtained are presented and discussed here.