Density functional theory study of Ni/Ni3Al interface alloying with Re and Ru

The optimal geometries and mechanical properties of (0 0 1) Ni/Ni3Al interface alloying with Re and Ru are studied using density functional theory. By placing alloying elements on cleavage or slip interface planes, brittle cleavage and generalized stacking fault energies are calculated for (0 0 1) interface. Simulated results indicate that the preferred slip direction is 〈1 1 0〉 in (0 0 1) plane. Re and Ru atoms preferred to substitute Al site of γ′ phase. Both of doping Re and Ru enhance the coherent strength of interface, and additions of Re are more effective in strengthening interface compared with Ru. Based on the criteria for ductile behavior, our results show that Re and Ru are good candidates for improving ductility of γ/γ′ superalloy.