Molecular dynamics simulations were used to investigate orientation and rate dependence of partial dislocation nucleation in Cu. As the strain rate was reduced from 109 to 107/s, the tensile stress required for homogeneous dislocation nucleation was reduced by at most 5%. Furthermore, mild orientation sensitivity was observed in the rate dependence of the critical tensile stress. The computed resolved shear stress for partial dislocation nucleation was consistent with previous ab initio calculations of the theoretical shear strength of Cu.

Orientation and Rate Dependence of Dislocation Nucleation Stress Computed using Molecular Dynamics. D.E.Spearot, M.A.Tschopp, D.L.McDowell: Scripta Materialia, 2009, 60[8], 675-8