Complex Hybrid Numerical Model in Application to Failure Modelling in Multiphase Materials

Development of a discrete/continuum numerical model of different failure modes operating in dual phase steels during deformation is the main goal of the research. Proposed approach is based on a random cellular automata (RCA) model incorporated in a fully coupled manner to the finite element (FE) framework. As a result, the RCAFE model that can take into account fracture initiation within martensite phase, delamination between martensite and ferrite phases, ferrite phase fracture and delamination between ferrite and ferrite grain boundaries was established. Details on the developed cellular automata model including random space definition, state of CA cells as well as properly defined transition rules are recapitulated in the work. Developed data bridging technique between RCA and FE models is discussed within that part. Particular attention, however, is put on model parameters identification stage, which was realized with the inverse analysis technique on the basis of in situ tensile tests. Finally, examples of model application to multiscale numerical simulation of three point bending, which was selected as a case study, are presented to highlight predictive capabilities of the developed RCAFE solution.