1600℃Mo-Si-C三元系组元化学势相图及其应用

Applications of Stabilized Chemical Potential Diagrams for Mo-Si-C Ternary System at 1600℃

收集并计算了Mo -Si-C三元系在 1 60 0℃下各组元化合物的热力学数据 .利用Mo -Si-C三元系在该温度下的平衡相图以及收集计算的该三元系的热力学数据 ,计算了该三元系中各组元的化学势并作出了相应的化学势稳定性相图 .讨论了热力学、物质平衡和动力学原则在固态置换反应原位合成复合材料中的应用 .这些原则应用于MoSi2 -SiC复合材料的原位合成 ,可以确定反应起始物的物种和成分 .原位合成MoSi2 -SiC复合材料的反应起始物为Mo2 C和Si.利用Mo -Si-C三元系 1 60 0℃下的平衡相图和组元化学势稳定性相图分析了固态置换反应原位合成MoSi2

The thermodynamic data of Mo-Si-C ternary system at 1?600℃ are collected and calculated. The equilibrium phase diagram of Mo-Si-C ternary system at 1?600℃ and the estimated unknown thermodynamic data of intermetallic compounds are utilized to calculate stabilized chemical potential and to draw the stabilized chemical potential diagrams of Mo-Si-C ternary system. The applications of the principles of thermodynamics, mass balance and kinetics to the synthesis of composites through solid-state displacement reactions have been discussed. Applying these principles to the synthesis of situ MoSi 2-SiC composites, it is shown that the proper starting reaction materials are Mo 2C and Si. The use of equilibrium phase diagram and stabilized chemical potential diagrams of Mo-Si-C ternary system at 1?600℃ for analyzing reaction paths of the synthesis of situ MoSi 2-SiC composites through solid-state displacement reactions is demonstrated.