Molecular dynamics simulations were used to investigate the response of a/2<111> screw dislocation in Fe submitted to pure shear strain. The dislocation glides and remains in a (110) plane; the motion occurred exclusively through the nucleation and propagation of double kinks. The critical stress was calculated as a function of the temperature. A new method was developed and used to determine the activation energy of the double kink mechanism from molecular dynamics simulations. It was shown that the differences between experimental and simulation conditions lead to a significant difference in activation energy. These differences were explained, and the method developed provides the link between molecular dynamics and mesoscopic simulations.

Simulation of Screw Dislocation Motion in Iron by Molecular Dynamics Simulations. C.Domain, G.Monnet: Physical Review Letters, 2005, 95[21], 215506 (3pp)