Crystal Plasticity Analyses Around Grain Boundaries Using a Dislocation Dynamics Finite Element Model

We setup a dislocation dynamics finite element framework by bridging a dislocation dynamics program and an open source finite element program. As part of initial verification, deformation of single crystal micro-pillar having single and double glide activation is demonstrated. A case study of a twin boundary is presented wherein the dislocation pile-up at the grain boundary and formation of a residual dislocation are shown. For studying the dislocation interactions with other grain boundaries, model grain boundaries are considered. We consider three synthetic grain boundaries namely transparent, semi-transparent, and impenetrable. The model’s transparent and semi-transparent grain boundaries contain no dislocations and very low density of dislocations in them, respectively, and thus low number of interactions with other dislocations. More junctions and cross-slip occurrences are recorded near the semi-transparent grain boundary. The most dislocation–dislocation interactions near grain boundaries result into glissile junctions. The current results are compared against literature data and it is observed that other than junction formation, cross-slip is very frequency observed near grain boundaries.