Calculating the melting curves by the thermodynamic data matching method: Platinum-group refractory metals (Ru, Os, and Ir)

Abstract

A technique for reconstructing thermal properties, including the melting curve, of refractory metals based on the use of experimental data on caloric properties available up to the melting point and some regularities of the Debye–Grüneisen theory has been proposed. The calculation result is the consistent system of high-temperature thermal data, including the thermal expansion coefficient, solid-phase density, and volume jump upon melting. This technique was tried-out on refractory platinum-group metals based on experimental data on the enthalpy of the metals and confirmed by consistency with a thermodynamic calculation using shock-wave experiments and results obtained by the quantum molecular dynamics method.