Microstructure-based deformation modeling of dual-phase steels

Dual-phase steels contain complex composite microstructure of ferrite and martensite phases that govern their mechanical behavior. Traditional analytical approaches of modeling the flow curve of composite microstructures of simplistic morphologies are therefore not able to capture the exact physics of deformation in totality. Therefore in order to model the flow behavior of such complex microstructures accurately, it is important to make the actual representation of microstructure to be a part of the model. The current work focusses on modeling the flow behavior of dual-phase steels using 2D representative volume element (RVE) based description of microstructure in FEM-based deformation models. Uniaxial deformation of actual microstructures is simulated under appropriate boundary conditions and the corresponding flow curve is calculated using first-order homogenization technique. While this type of analysis is reported in the literature, choices made for simulation parameters and assumptions may result in diverse outcomes. Therefore, in an effort to characterize this technique, a comparative study is conducted between plane strain and plane stress assumptions used for 2D RVE deformation modeling. Based on the studies, we have compared the efficacies of both the approaches and made our observations.