The mechanical behavior of a low alloy multiphase TRIP steel has been predicted by an advanced microstructure-based finite element method. A representative volume element chosen based on the actual microstructure has been utilized for simulating the mechanical behavior of the studied steel. The parameters describing the martensitic transformation kinetics have been estimated using both crystallographic and thermodynamic theories of martensitic transformation. The mechanical behavior of each of the constituent phases required for the prediction of mechanical behavior of the studied material has been extracted from those reported in the literature. Comparison of the predicted mechanical behavior of the investigated TRIP800 steel with those reported in the literature shows that there is good agreement between simulated and experimental results. Therefore, it can be said that, the utilized microstructure-based model can be used for the prediction of both mechanical and transformation behaviors of the TRIP800 steels. It is worth noting that all of the parameters used in the model, except the sensitivity of the martensitic transformation to the stress state, can be estimated theoretically; thus, the number of parameters obtained by correlating the simulated and experimental results reduces to one. This is the unique characteristic of the utilized model, which makes the application of the model for simulation of the mechanical behavior of TRIP steels simpler than that of the similar ones.

Keywords