An atomistic modelling framework was developed in order to address the probabilistic nature of surface dislocation nucleation. It was shown that the activation volume which was associated with surface dislocation nucleation was characteristically in the range of 1 to 10b3, where b was the Burgers vector. Such small activation volumes led to a sensitive temperature and strain-rate dependence of the nucleation stress, thus providing an upper bound on the size-strength relationship in nanopillar compression experiments.

Temperature and Strain-Rate Dependence of Surface Dislocation Nucleation. T.Zhu, J.Li, S.Samanta, A.Leach, K.Gall: Physical Review Letters, 2008, 100[2], 025502