Direct atomistic simulations of dislocation multiplication in face-centered cubic Al revealed an unexpected mechanism, in which a Frank-Read source emitted dislocations with Burgers vectors different to that of the source itself. The mechanism was traced to the spontaneous nucleation of partial dislocation loops within the stacking fault. Understanding and a quantitative description of this unusual process were achieved through the development of a continuum model for dislocation nucleation based upon the coarse-grained dislocation dynamics approach and a minimal amount of atomistic input.

Anomalous Dislocation Multiplication in FCC Metals. M.de Koning, W.Cai, V.V.Bulatov: Physical Review Letters, 2003, 91[2], 025503 (4pp)