Grain boundary dislocation sources in nanocrystalline copper

Atomistic simulations of dislocation nucleation from grain boundaries provide an insight into dislocation sources in nanocrystalline copper. Simulations show that dislocation sources emit single partial dislocation loops, with half absorbed into the boundary and half emitted into the lattice. The specific boundary dislocation content determines whether the absorbed half-loop annihilates pre-existing boundary dislocations or increases boundary dislocations. Atomistic studies of this type provide details of the emission sequence that enhance our understanding of dislocation sources in high angle boundaries.