Fatigue resistance of deep drawn parts: A scale bridging simulative study using representative volume elements and crystal plasticity simulations

The mechanical properties of formed components are determined by the interaction between the microstructure and the load path of the forming process. To investigate and understand these effects, micromechanical simulation concepts can be used, such as statistically Representative Volume Elements (sRVE) coupled with crystal plasticity simulations. This study presents a concept that uses sRVE simulations to quantify the influence of three different deep drawing load paths on the fatigue resistance of DP800 steel. The first step is a scale-bridging simulation approach that employs macroscopic simulations of the deep drawing process to extract the boundary conditions for the sRVE simulations with Damask. Subsequent cyclic loading is then simulated. 50 sRVE are computed for each load path to estimate fatigue resistance based on a Fatigue Indicator Parameter. The results indicate that fatigue resistance increases with increasing deformation-induced strain hardening. Additionally, a positive correlation between the martensitic ligament structures and fatigue resistance was observed.