The influence of doping by transition metal elements on the vacancy formation energy in Fe-Al B2 phase

Abstract

Based on ab initio calculations for Fe-Al B2 phase with and without the vacancies, the authors studied the influence of alloying by Ni, Cr, and V on the energy of vacancy formation. The authors predict that the presence of these alloying elements in the vicinity of the vacancy on the Fe site increases the energy of the vacancy formation. The present article discusses the changes of the electron charge redistribution in the vicinity of the vacancy in Fe-Al alloyed with these transition metals and link the preference of their site occupation with the peculiarities of the electron density redistribution. In addition, the authors report on the results of calculations of different types of antisite defects in Fe-Al and show that the formation of the antisite on the Al site is the energetically preferable configuration for this defect. The obtained results are in agreement with the experimental data.

First-principles study on the site preference of Dy in B2 NiAl

“…For Dy, the ultrasoft pseudopotential with 20 electrons including the 4f shell is treated as valance electrons [31]. The 16-atom 2 × 2 × 2 cubic B2 NiAl supercell was adopted for all the calculations [32][33][34][35].…”

Influence of alloying on the thermodynamic stability of FeAl B2 phase

“…Presence of these defects in FeAl has significant influence on the material properties stimulating the research aimed to use peculiar defect behaviour for improving material performance [3e6]. We found, in our previous works, that the vacancies exist mainly on the Fe sublattice [7] and the anti-sites are more feasible energetically on the Al sublattice [8] in FeAl B2 phase. These results are in agreement with experimental and theoretical studies [9e11].…”