In this work, a thermodynamic treatment for (Th,U)O₂ and (Th,Pu)O₂ fuels has been developed using the CALPHAD method to describe phase diagram and thermodynamic data of the phases in the Th-U-Pu-O sub-systems. The treatment builds on previously reported assessments of the U-Pu-O ternary oxide system and of the Th-U-Pu ternary metallic system. The thermodynamic and phase diagram properties calculated by the models herein are in good agreement with available experimental data for the binary and ternary subsystems, as well as new phase diagram data for the Th-O binary reported here. This treatment is useful to predict thermodynamic behavior of thoria-based nuclear fuels at various temperatures and compositions.

在这项工作中，已开发出使用CALPHAD方法对（Th，U）O ₂和（Th，Pu）O ₂燃料进行热力学处理，以描述Th-U-Pu-O中各相的相图和热力学数据。子系统。该处理基于先前报告的对U-Pu-O三元氧化物系统和Th-U-Pu三元金属体系的评估。由本文模型计算的热力学和相图性质与二元和三元子系统的可用实验数据以及此处报告的Th-O二元的新相图数据非常一致。该处理对于预测基于氧化ria的核燃料在各种温度和组成下的热力学行为是有用的。