Models for Austenite to Martensite Transformation in TRIP-Aided Steels: A Comparative Study

Low alloy transformation induced plasticity (TRIP)-aided steels are of particular interest to the automotive industry as they offer an excellent combination of strength and ductility at affordable costs. These unique properties depend primarily on the deformation induced transformation behavior of retained austenite to martensite, which is therefore, the most important aspect of TRIP-aided steels. As such, it is important to develop a mathematical model for the transformation of retained austenite. This would not only help in a better understanding of the deformation induced transformation behavior of retained austenite but also aid in a better design of the microstructure of TRIP-aided steels. A large number of empirical as well as semi-empirical models have been developed over the years to describe and predict the variation of retained austenite with strain. A comparative study of the different available models will be presented in this article.