CuO对Ti-C-Al体系自蔓延反应过程的影响

Effect of CuO on the self-propagating reaction process of Ti-C-Al systems

选择Ti--C--Al和Ti--C--Al--CuO两种体系,采用原位反应近液相线铸造技术,制备铝基复合材料.通过金相显微镜、扫描电镜和X射线衍射仪研究了复合材料的微观组织.对上述两种体系的反应进行了热力学与动力学分析.进一步研究了CuO对Ti--C--Al体系的自蔓延反应过程的作用机理,建立了其反应过程的动力学模型.结果表明:在Ti--C--Al体系自蔓延反应过程中,CuO和Al的反应可以提高其反应体系的绝热温度,能为该体系反应持续提供热量,使其自蔓延效果更为显著,反应更加彻底,大大减少条块状的中间产物Al3Ti,优化了材料组织.

Aluminum matrix composites were prepared using an in-situ reactive near-liquidus casting technique in two systems of Ti-C-Al and Ti-C-Al-CuO. Their microstructure was studied by optical microscopy, scanning electron microscopy and X-ray diffraction. Thermodynamic analysis on the reaction in the two systems was carried out. The effect of CuO on the self-propagating reaction process of the Ti-C-Al system was discussed, and a kinetic model was set up. It is found that in the self-propagating reaction process of the Ti-C-Al system, the reaction between CuO and Al is able to enhance the adiabatic temperature of the system and provide the system with sustaining heat, making the self-propagating reaction more remarkable and more completed. As a result, blocky Al3 Ti mesophase is ex-tremely decreased, and the microstructure of the composites is optimized.