C01 – Multiphysics Description of Metal-Intermetallic Composites at the Grain Scale

PIs: Sandlöbes-Haut, Stefanie (RWTH Aachen University); Roters, Franz (MPIE)

SFB researcher: Liu, Chuanlai (MPIE)

Project C01 focuses on the co-deformation of a solid solution matrix reinforced with an intermetallic phase skeleton using crystal plasticity simulation and deformation experiments. The role of deformation twinning and the intermetallic phase on the plastic deformation mechanisms and the mechanical performance of Mg composite alloys is systematically investigated in this project.
We have developed a mechanical formulation within the finite strain framework for modelling dislocation slip- and deformation twinning-induced plasticity. A dislocation density-based crystal plasticity model was used to describe the dislocation activities, and the stress and strain distributions. The model was coupled with a multi-phase-field model to predict twin formation and twin-twin interactions. The model was then employed to study twin, dislocation, and grain boundary interactions in Mg single- and polycrystals during monotonic and cyclic deformation. Furthermore, based on the experimental characterization of the mechanical properties and the microstructure of the intermetallic phase, we have studied the effect of the volume fraction, morphology, stiffness, and elasto-plastic properties of the intermetallic phase on the overall mechanical properties and the local stress and strain distribution of Mg composite alloys.