Atomistic computer simulations were performed to investigate the mechanisms of grain-boundary sliding in body-centred cubic Fe using molecular statics and molecular dynamics with embedded-atom method interatomic potentials. For this study, the Σ = 5 (310)[001] symmetrical tilt boundary was chosen, with a tilt angle of 36.9°. Sliding was shown to be governed by grain-boundary dislocation activity with Burgers vectors belonging to the displacement shift complete lattice. The sliding process was found to occur through the nucleation and glide of partial grain-boundary dislocations, with a secondary grain-boundary structure playing an important role in the sliding process. Interstitial impurities and vacancies were introduced into the grain boundary to study their role as nucleation sites for the grain-boundary dislocations. While vacancies and H interstitials act as preferred nucleation sites, C interstitials did not.

Atomistic Sliding Mechanisms of the Σ = 5 Symmetric Tilt Grain Boundary in BCC Iron. B.Hyde, D.Farkas, M.J.Caturla: Philosophical Magazine, 2005, 85[32], 3795-807