Modelling austenite flow curves in low alloy and microalloyed steels

Abstract

A model has been developed to predict the austenite flow curves of low alloy and microalloyed steels. The model consists basically of two expressions for stress, as a function of strain, temperature, strain rate and the chemical composition of the steel. The first predicts the hardening and dynamic recovery region and the second predicts the softening caused by dynamic recrystallization, the algebraic sum of both expressions predicting the complete flow curve. The model's different parameters are a function of the dimensionless parameter of Sellars and Tegart's equation, which in turn has been modelled not only as a function of temperature and strain rate but also as a function of the chemical composition. In this way one single model may be applied to any hot deformed steel whose composition is the same as or similar to those studied.