Defects in free surfaces were expected to be seeds for the nucleation of dislocations; which was the probable manner in which nanoscale materials suffered plastic deformation. Such nucleation resulted in a competition between the image force, which attracted the dislocation to the surface, and the applied strain. Two methods based upon molecular dynamics simulations, using an embedded atom method potential, were used to determine the activation energy and the critical radius for the formation of dislocations from a surface defect in a typical face-centered cubic metal.

Determination of Activation Parameters for Dislocation Formation from a Surface in FCC Metals by Atomistic Simulations. P.Hirel, J.Godet, S.Brochard, L.Pizzagalli, P.Beauchamp: Physical Review B, 2008, 78[6], 064109