Al-MoSi_2-TiC陶瓷基复合材料的研究

RESEARCH ON Al-MoSi_2-TiC CERAMIC MATRIX COMPOSITES

研究了Al-MoSi2-TiC陶瓷基复合材料的烧结工艺;利用MoSi2高温蠕变的特性促进TiC粉料的高温烧结;探讨了添加少量的金属铝粉对复合材料力学性能的影响;用SEM扫描电镜和X-射线衍射对复合材料显微形貌和晶体结构进行了表征。结果表明,MoSi2降低了TiC的烧结温度;制备的复合材料中除了TiC之外,还生成了新物相Mo2C,TiSi2和C;金属铝均匀分布在复合材料基体中,明显提高了材料的力学性能,抗折强度由50MPa提高到90MPa,抗压强度由55MPa提高到180MPa,同时其热膨胀系数随Al增加逐渐增大;讨论了Al-MoSi2-TiC陶瓷基复合材料的断裂机理。

In this paper, the sinter technology for making AI-MoSi2-TiC ceramic matrix composites was studied. TiC powder is easily sintered by virtue of deformation of MoSi2 at high temperature; the effect of AI on the mechanics performance of composites was investigated; micro graphics and crystal structure were demonstrated by SEM and X-Ray. Results indicated that new materials were obtained and sinter temperature was lowered; AI was proportionately distributed in MoSi2-TiC ceramic matrix composites and the materials had excellent mechanical capability; flexural strength was increased from 50MPa to 90MPa and compressive strength from 55MPa to 180MPa; also expansion coefficient was obviously increased with AI powder content; the fracture mechanism of Al-MoSi2-TiC ceramic matrix composites was also discussed.