The Thermodynamic Properties Of The Rare Earth Ternary Alloys Studied With EAM

The rare earth alloys are important functional materials, so more and more attentions have paid to rare earth alloys. However, the experimental thermodynamic data for rare earth alloys are not complete due to the experimental difficulties. It is important to calculate and simulate the thermodynamic properties of the rare earth elements and alloys with theoretic models. Daw and Baskes have proposed the embedded atom method based on density functional theory. Embedded atom method has been applied to investigate the thermodynamic properties of alloys successfully. In this work, the parameters of embedded atom method for elements Al, Ce, Th and Yb have been determined by fitting the lattice constants, the cohesive energy, the monovacancy formation energy and the bulk modulus of elements. For Ce-Th-Yb alloy system, the alloy potential has been taken as the form of Johnson's. The formation enthalpies of Th-Ce, Th-Yb and Ce-Yb binary alloys systems and Ce-Th-Yb ternary alloy have been calculated with the present embedded atom potentials. The heats of dilute solution for Th-Ce, Ce-Th, Th-Yb, Yb-Th, Ce-Yb and Yb-Ce binary alloys systems have been calculated. For Al-Ce-Yb ternary alloy system, the parameters φ_e of alloy potentials for Al-Ce and Al-Yb which we proposed have been determined by fitting the formation enthalpies of Al₂Ce and Al₂Yb. The formation enthalpies of Al-Ce and Al-Yb binary alloys systems and Al-Ce-Yb ternary alloy have been predicted. The heats of dilute solution of Al-Ce, Ce-Al, Al-Yb, Yb-Al binary alloys systems, and the lattice constants, the elastic constants, the cohesive energy and the formation enthalpies for intermetallic compounds (AlCe, Al₂Ce, AlCe₃, Al₂Yb, Al₃Yb)...