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.

通过实验研究和热力学计算，对 La-Pr-Fe 和 Ce-Pr-Fe 三元体系的相平衡和凝固行为进行了研究。通过差热分析（​​DTA）和具有能量色散光谱的扫描电子显微镜（SEM-EDS）研究了La-Pr-Fe和Ce-Pr-Fe三元合金的相变温度和凝固组织。基于本文确定的实验结果和文献报道，采用CALPHAD方法计算了La-Pr-Fe和Ce-Pr-Fe三元体系，得到了这两个三元体系的合理热力学参数. La-Pr-Fe和Ce-Pr-Fe三元体系的计算等温截面和垂直截面与实验结果吻合良好。