Integrating Microstructural Damage Characterization with Elasto-Plastic FE Modeling to Assess Damage-Induced Property Changes in DP800
Please login to view abstract download link
Establishing a quantitative connection between void evolution and the measured macroscopic material response remains challenging, because damage evolves alongside other mechanisms, in particular strain hardening and residual stresses, throughout plastic deformation. This study combines a data-driven damage evolution model with high-resolution scanning electron microscopy measurements of void area fractions in dual-phase steel DP800. By incorporating the data-enriched evolution law into an elasto-plastic finite element framework, the damage-induced degradation of the apparent elastic stiffness can be investigated. The formulation combines Hill-type anisotropic plasticity with isotropic hardening and a Young’s modulus that depends on both strain hardening and damage evolution in the form of microscopic void growth. Finite element simulations of tensile tests with loading–unloading–reloading sequences show that the early decrease in apparent elastic stiffness is not caused by void-related damage. Even at large plastic deformation prior to macroscopic fracture, the predicted void area fractions remain too small to induce a detectable stiffness reduction within the present framework. Overall, for the investigated DP800 material and the considered loading path, the contribution of the measured void evolution to apparent stiffness degradation and macroscopic softening is negligible, indicating that alternative mechanisms must dominate the experimentally observed stiffness changes.
