Modeling of molar volume for the Ni–Al γ/γ′ binary phases within the framework of CALPHAD method

Abstract Assisted by the first-principles calculations, the molar volumes of γ and γ′ phases in the binary Ni–Al system were modeled within the framework of the CALPHAD method. A CALPHAD database integrating thermodynamic and molar volume descriptions was established. The present Ni–Al binary database was validated to make good predictions of molar volumes/lattice parameters and thermal expansivities for both γ and γ′ phases. The predicted γ/γ′ lattice misfits from low to high temperatures turn out to be reasonable.