(335b) Liquid-Vapor and Liquid-Liquid Phase Equilibria in Binary Alloys with Modified Quantum-Corrected Sutton-Chen Potentials

The embedded atom method (EAM) has been extensively used to study metallic systems, and many different EAM potentials have been proposed, built from different functional forms and parameterized against different experimental and/or ab initio data, such as lattice constants, elastic constant, cohesive energies, and cluster structures.  We consider here phase equilibria and thermophysical properties in binary alloys as modeled by the quantum-corrected Sutton-Chen potential (qSC) [1] and various mixing rules for unlike-element interactions [2].  Calculations of the enthalpy of mixing show that standard mixing rules do not generally agree well with experimental data [3-5]. We empirically determine modified cross-interactions which give satisfactory agreement, and consider how improved mixing rules may be developed for this class of systems.  Using these improved potentials we then make predictions of liquid-vapor and liquid-liquid phase envelopes and other phase boundaries in selected systems.

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