Thermodynamic assessment of the constitutive binaries of the NaCl-KCl-UCl₃-PuCl₃ system was carried out by CALPHAD (CALculation of PHase Diagrams) approach. The liquid phase was described by the substitutional solution model, and the intermediate compounds were treated as stoichiometric phases. The thermodynamic parameters of the binary systems were obtained based on experimental phase equilibria data available in the literature and theoretical prediction data by first-principles calculations and empirical equations. A set of self-consistent thermodynamic parameters for each of the binary system was finally obtained. Some representative liquidus surface projections, isothermal sections and pseudo-binary phase diagram for the sub-ternary and quaternary systems were calculated by model extrapolation. The influence of KCl on the thermodynamic behavior of NaCl-UCl₃-PuCl₃ matrix salt was analyzed. The extrapolated results indicated that KCl can be used as a candidate additive component of NaCl-UCl₃-PuCl₃ matrix salt from the point of view of thermodynamics. This study provided a comprehensive understanding for the thermodynamic behavior of a candidate molten salt fast reactor nuclear fuel and a fundament for the design of nuclear fuel.

所述的组成的二进制文件的热力学评估的NaCl-KCl的-UCL ₃ -PuCl ₃系统通过CALPHAD（相图的计算）方法进行。用替代溶液模型描述了液相，并将中间化合物视为化学计量相。基于文献中提供的实验相平衡数据和通过第一原理计算和经验方程式得到的理论预测数据，获得了二元系统的热力学参数。最终获得了每个二元系统的一组自洽热力学参数。通过模型外推计算了一些代表性的液相线表面投影，等温截面和伪二元相图。氯化钾上的热力学行为的影响NaCl的UCL ₃ -PuCl ₃分析基质盐。外推的结果表明，氯化钾可以用作NaCl的UCL的候选添加剂组分₃ -PuCl ₃但从热力学点矩阵盐。这项研究为候选熔盐快堆核燃料的热力学行为提供了全面的了解，并为核燃料设计提供了基础。