The mobility of vacancies and interstitials trapped on a dissociated edge dislocation in copper was studied by molecular dynamics. Although fast diffusion was thought to occur exclusively in a pipe surrounding the dislocation core, in the present study a quasi-two-dimensional diffusion was observed for defects not only in the cores but also in the stacking fault ribbon. Contrary to current assumptions, the activation energy for diffusion was found to be identical for both defects, which may therefore comparably contribute to mass transport along the dislocations.

Is Pipe Diffusion in Metals Vacancy Controlled? a Molecular Dynamics Study of an Edge Dislocation in Copper. Huang, J., Meyer, M., Pontikis, V.: Physical Review Letters, 1989, 63[6], 628-31

Table 11

Self-diffusivity in [001] Cu twist grain boundaries