The atomic structure and mechanism of the interface sliding of the Σ = 5(210)[001] symmetric tilt grain boundary in Cu and its interaction with vacancies at an elevated temperature was studied using a computationally efficient potential based on the Embedding Atom Method in connection with the finite temperature Monte Carlo technique. Grain boundary sliding was performed for pure Cu as well as Cu containing a vacancy at a selected position. The discontinuous changes of the grain boundary energy at certain sliding distances were associated with grain boundary migrations. Elevated temperature reduces the grain boundary sliding/migration energy by a factor of about 2 but did not increase the rate of migration. Migration of the grain boundary was mediated by the flow of atoms along the interface in coordination with the atoms in bulk. The sliding and migration properties partially depend on the position of the vacancy in the grain boundary core. It was found that the grain boundary sliding energy profile in the presence of a vacancy placed at the interface increased the grain boundary energy, but reduced the sliding energy. The sliding process invokes the interface migration in such a way that the vacancy effectively migrates to a more convenient position and reduces the grain boundary energy.

Grain Boundary Sliding and Migration in Copper - the Effect of Vacancies. P.Ballo, V.Slugeň: Computational Materials Science, 2005, 33[4], 491-8