Mixing Enthalpies of Melts and Thermodynamic Assessment of the Cu–Fe–Cr System

Abstract

The mixing enthalpies of ternary liquid alloys in the Cu–Fe–Co system have been studied by calorimetric method at 1873 K and x Cr = 0–0.45. The phase transformations in the Cu–Fe–Cr system have been examined using methods of physicochemical analysis. The thermodynamic assessment of the ternary system has been carried out in the framework of the CALPHAD method. The set of self-consistent parameters for thermodynamic models of the phases has been obtained taking into account experimental data of the present work and information on phase transformations. The isothermal and vertical sections of the phase diagram, liquidus and solidus surfaces, as well as metastable miscibility gaps of supercooled liquid alloys have been calculated. The degrees of supercooling for metastable liquid phase immiscibility have been assessed. The composition ranges for the formation of alloys with special structures have been predicted. The temperature–composition ranges for the formation of supersaturated solid solutions during liquid quenching have been evaluated.