Effects of alloying elements in popular steels on the oxidation and dissolution corrosion of the surface of γ-Fe(111) have been investigated by performing density functional theory calculations within the local density approximation. First, the segregation of alloying atoms as well as preferential adsorption sites for oxygen and water were carefully examined, and it was found that all of the alloying elements considered had a tendency to segregate to the surface, and that the most preferred adsorption sites were the hexagonal closed packed (hcp) site and the top site for oxygen and water, respectively. The adsorption energies that characterized the tendency for oxygen or water to be adsorbed on the alloy surface showed that all ten alloying elements (especially Cr, Si, and Cu) were able to inhibit the adsorption of oxygen, and that all of the alloying elements except for Nb, Mo, and Ti inhibited water adsorption. The electrode potentials, which indicate the electrochemical stabilities of the surfaces of the alloys, suggested that all of these alloying elements (especially Cr, Mo, and Si) were able to suppress the adsorption of oxygen and water on the investigated surfaces, except for Nb and Ti in the case of water adsorption. Density of states analysis further indicated that all ten alloying elements (especially Cr, Si, Mo, and Cu) enhanced the corrosion resistance of the fcc Fe substrate, except for Nb and Ti with respect to dissolution corrosion.

This study investigated the structural stability and electrochemical properties of alloying additives M (M = Mn, V, Ti, Mo, or Ni) at the γ-Fe(111)/Cr₂N(0001) interface by the first-principles method. Results indicated that V and Ti were easily segregated at the γ-Fe(111)/Cr₂N(0001) interface and enhanced interfacial adhesive strength. By contrast, Ni and Mo were difficult to segregate at the γ-Fe(111)/Cr₂N(0001) interface. Moreover, the results of the work function demonstrated that alloying additives Mn reduced local electrochemical corrosion behavior of the γ-Fe(111)/Cr₂N(0001) interface by cutting down Volta potential difference (VPD) between clean γ-Fe(111) and Cr₂N(0001), while alloying additives V, Ti, Mo, and Ni at the γ-Fe(111)/Cr₂N(0001) interface magnified VPD between clean γ-Fe(111) and Cr₂N(0001), which were low-potential sites that usually serve as local attack initiation points.

The addition of B can inhibit the precipitation of σ phases at the grain boundary to improve the hot workability and corrosion resistance for super austenitic stainless steel with high Cr and Mo content. This study focused on the interaction between B and Mo at the Fe–Cr(111)/Cr₂O₃(0001) interface and its effect on interfacial adhesion by employing the first-principles method, especially the effect of B on the segregation behavior of Mo. The most stable O-terminated Fe/Cr₂O₃ interface was chosen as the basic configuration. The segregation energy and the work of separation were calculated for the metal/chromia interface with Fe–Cr as the substrate. It has been demonstrated that B can promote the diffusion of Mo atoms into the oxide layer to increase the content of Mo in the passive film. In addition, the interfacial adhesion is higher at the most segregated sites. However, it is more difficult for two or more Mo atoms than a single Mo atom to diffuse into the oxide part with the effect of B, indicating that B can only improve the Mo content of the passive film to a small extent. The electronic properties were also further discussed to analyze the interactions and the binding characters between doped atoms and their surrounding atoms and to explain the underlying reasons for the variation of interfacial adhesion.