Thermodynamic calculation and solidification behavior of the La-Pr-Fe and Ce-Pr-Fe ternary systems

Phase equilibria and solidification behavior of the La-Pr-Fe and Ce-Pr-Fe ternary systems were carried out through experimental investigation and thermodynamic calculation. Phase transition temperatures and solidification microstructure of La-Pr-Fe and Ce-Pr-Fe ternary alloys were studied by means of differential thermal analysis (DTA) and scanning electron microscopy with energy dispersive spectra (SEM-EDS). Based on the experimental results determined in this work and reported in the literature, the La-Pr-Fe and Ce-Pr-Fe ternary systems were calculated by the CALPHAD method, and reasonable thermodynamic parameters of these two ternary systems were obtained in this work. The calculated isothermal section and vertical section of the La-Pr-Fe and Ce-Pr-Fe ternary systems are in good agreement with the experimental results. The solidification processes of as-cast La-Pr-Fe and Ce-Pr-Fe ternary alloys were analyzed through thermodynamic calculation with Scheil model, which is satisfactorily consistent with the experimental solidification microstructure.