E. Zhurkin

The features of the cascade of atomic collisions, the spatial distribution of dopes, and primary radiation damage in a near-surface region of cubic silicon carbide under bombardment by Si (N) ions and clusters (N = 1, 5, and 60) in the case of the same energy per one atom of the particle-projectile (200 and 1000 eV/atom) are studied in this paper. The study is carried out using classical molecular dynamics. As a result, several features of the low-energy implantation of polyatomic clusters in SiC(111) are revealed, namely, a relatively weak effect of the size of the implanted cluster on the distribution of ranges of incorporated atoms, a low degree of nonlinear effects at the cascade and postcascade stages, and formation of amorphous regions in the target during cluster implantation.

In this work, the Metropolis Monte Carlo (MMC) method employing the isothermal–isobaric statistical ensemble is applied to investigate segregation at grain boundaries in bcc Fe–Cr alloys with varying Cr content from 5 to 14 at.%. Several different 〈1 1 0〉 tilt grain boundaries, namely: Σ19{3 3 1}, Σ9{2 2 1}, Σ3{1 1 1}, Σ3{1 1 2}, Σ11{1 1 3}, Σ9{1 1 4} with misorientation angle varying in the range 26–141° were considered. Systematic MMC simulations were performed employing a two band empirical many-body potential in the temperature range 300–900 K. It was found that the binding energy of substitutional Cr to the GB core is essentially determined by the structure of the GB interface and varies in the range 0.05–0.35 eV. At this, the binding energy increases with the GB excess volume. MMC simulations revealed that either a local atomic rearrangement or segregation of Cr at the considered GBs occurs depending on the combination of temperature, alloy composition and GB structure. Influence of temperature and GB structure on the local atomic rearrangement and precipitation of α′ particles is demonstrated.