Site preference of alloying elements in Fe3Al-based alloys

On the basis of the first principle interatomic potentials, the site prefer ence of various alloying elements in Fe3Al were evaluated for Ti, Si, Ni, M n, Mo, and Cr, respectively. The calculated results of the substitutional d istribution were in good agreement with the experimental results. Moreover, the calculated results showed that H atoms in Fe3Al prefer to occupy the F e-type octahedral interstice on the surface, which resulted in concentratio n of H atoms on the surface. Cr addition decreased the absorbability of Fe3 Al-based alloys for H atoms and the force to drive H atoms segregating to s urface. The concentration of H atoms on the surface can be decreased by Cr addition.