Phase stability and elastic properties of Al-Pr intermetallic compounds from first principles calculations

To develop a better understanding of the phase stability and elastic properties of the Al-Pr intermetallic compounds, the lattice parameters, enthalpy of formation, and cohesive energy and elastic modulus of the Al-Pr intermetallic compounds were investigated by using first-principles calculations based on density functional theory. The calculated equilibrium lattice parameters are by available experimental values. The thermodynamic properties were discussed and analyzed with an energy minimum approach in terms of structural stability. The results reveal that the Al2Pr intermetallic compound has the strongest alloying ability. & alpha;-AlPr intermetallic compounds show a minimum of cohesive energy. The results of the elastic modulus calculation show that the intermetallic compound & alpha;-AlPr3 behaves with the biggest anisotropy, and the intermetallic compound Al2Pr tends to be isotropic.