A ternary Ni–Al–W EAM potential for Ni-based single crystal superalloys

Based on experiments and first-principles calculations, a ternary Ni–Al–W embedded-atom-method (EAM) potential is constructed for the Ni-based single crystal superalloys. The potential predicts that W atoms do not tend to form clusters in γ(Ni), which is consistent with experiments. The impurity diffusion of W in γ(Ni) is investigated using the five-frequency model. The diffusion coefficients and the diffusion activation energy of W are in reasonable agreement with the data in literatures. By W doping, the lattice misfit between the two phases decreases and the elastic constants of γ′(Ni3Al) increase. As for alloyed elements Co, Re and W, the pinning effect of solute atom on the γ(Ni)/γ′(Ni3Al) misfit dislocation increases with the increasing of the atomic radius.