Interstitial clusters on Σ = 11(113) grain boundary in copper: Geometric structure, stability, and ability to annihilate vacancies

Abstract

The properties of interstitial clusters on Σ=11(113) grain boundary (GB) in copper are studied by first-principle calculations. The results show that the interstitial atoms on GB plane energetically tend to accumulate into a cluster. The geometric structures of interstitial clusters prefer to present in a line along the direction [11¯0] on Σ=11 GB plane if the grain boundary and neighbor lattices remain undamaged, and the stability of clusters increases with their elongation. The ability of interstitials in clusters to annihilate vacancies is decreased compared with isolated interstitials, however, interstitial clusters still could efficiently heal vacancies within a certain distance from grain boundary.