以铌或钼为基的合金可同时包含室温增韧相、高温增强相、抗环境氧化相等，其中各组成相的合理匹配能使喷气式发动机的高温部件在更高的温度下以更高的效率运行。目前的研究重点正朝着多元复相材料体系的方向发展，随之对相关的相平衡关系、相图热力学和合金化原理等基础信息提出了迫切的需求。本项目将重点针对Mo-Nb-Si-X(X=B,Cr,Hf/W)多元合金体系，通过相平衡实验和热力学优化，建立热力学数据库。并在此基础上，开展高稳定性多相平衡共存组织的理论预测与实验研究。系统深入地分析Nb/Mo-Si基超高温合金体系中可供协同调控增韧、增强、抗氧化的合金元素优化组合和相互作用影响程度，以及原位获得理想微观结构的有效形成条件和组织演化规律，取得相平衡计算和相组成设计的紧密关联。进而为开展Nb/Mo-Si基多元超高温合金材料的合金设计、组织控制和工艺优化等提供必要的相平衡实验数据和热力学理论基础。

The Nb/Mo-based alloys may consist of co-existed phases to improve the room-temperature toughness, the high-temperature strength, and the oxidation resistance, respectively. The reasonable match of these constituent phases can make the high-temperature components of the jet engines run hotter and more efficiently. In the train of the recent research, which focuses on the development of the materials composed of multi-components and co-existed phases, the fundamental investigation on the related phase equilibria, thermodynamics and alloying principles is becoming a more and more active demand. In the present project, the Mo-Nb-Si-X (X=B,Cr,Hf/W) systems are typically concerned. On the basis of the phase equilibrium measurement and the thermodynamic assessment, the interested thermodynamic database will be developed. Furthermore, the theoretical prediction and the experimental study on the highly stable microstructure of the co-existed multi-phases will be carried out. The systematic and deepening analysis for the Nb/Mo-Si based high temperature materials will be concentrated on the optimum combination and interaction influence of the alloying elements, as well as on the effective formation and transformation evolution of the in-situ microstructure, to promote toughening, strengthening and anti-oxidation ability. As a result, the close correlation between the analysis of phase equilibria and the design of phase constituents can be obtained. The further investigation is expected to provide the experimental data and scientific basis for the related alloy design, microstructure control and process optimization of the multi-components Nb/Mo-Si based high temperature materials.