Mesoscopic analysis of structure and strength of dislocation junctions in fcc metals

We develop a finite-element-based nodal dislocation dynamics model to simul ate the structure and strength of dislocation junctions in fcc crystals. Th e model is based on anisotropic elasticity theory supplemented by the expli cit inclusion of the separation of perfect dislocations into partial disloc ations bounding a stacking fault. We demonstrate that the model reproduces in precise detail the structure of the Lomer-Cottrell lock already obtained from atomistic simulations. In light of this success, we also examine the strength of junctions culminating in a stress-strength diagram which is the locus of points in stress space corresponding to dissolution of the juncti on.