Molecular dynamics simulations of 50 Fe grain boundaries were used to understand their interaction with vacancies and self-interstitial atoms, which was important for designing radiation-resistant polycrystalline materials. Site-to-site variation of formation energies within the boundary was substantial, with the majority of sites having lower formation energies than in the bulk. Comparing the vacancy and self-interstitial atom binding energies for each site showed that there was an energetic driving force for interstitials to preferentially bind to grain boundary sites over vacancies.

Energetic Driving Force for Preferential Binding of Self-Interstitial Atoms to Fe Grain Boundaries over Vacancies. M.A.Tschopp, M.F.Horstemeyer, F.Gao, X.Sun, M.Khaleel: Scripta Materialia, 2011, 64[9], 908-11