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研究了热循环对ＳｉＣｐ／ＭｏＳｉ_２复合材料抗弯强度和断裂韧度的影响，并测定了材料的宏观残余应力。实验材料是用热压方法制备的ＭｏＳｉ_２和不同体积百分数（１０，２０，３０ｖｏｌ％）ＳｉＣ_ｐ增强ＭｏＳｉ_２复合材料。实验结果表明，复合材料的抗弯强度和断裂韧度都随ＳｉＣ含量的增加而增加，经过热循环以后，四种材料的抗弯强度都有不同程度的增加，而断裂韧度则下降约２０％左右。这是由于材料经过热循环以后，造成ＳｉＣｐ和ＭｏＳｉ２界面结合过强和基体晶界过弱。尽管ＳｉＣ_ｐ和ＭｏＳｉ_２热膨胀系数相差很大，但在复合材料中未发现由此而产生的裂纹和宏观残余应力。
The effect of thermal cycling on the flexural strength and fracture toughness of SiCp / MoSi_2 composites was investigated. The macroscopic residual stress of the composites was also measured. The experimental materials were MoSi_2 prepared by hot pressing and MoSi_2 reinforced composites with different percentages of SiC_p (10,20,30vol%). The experimental results show that both the flexural strength and the fracture toughness of the composites increase with the increase of SiC content. After thermal cycling, the flexural strength of the four materials all increase to some extent, while the fracture toughness decreases about 20 %about. This is due to the material after thermal cycling, resulting in strong bonding SiCp and MoSi2 interface and the matrix grain boundary is too weak. Although the coefficients of thermal expansion of SiC_p and MoSi_2 are very different, no cracks and macroscopic residual stresses are found in the composites.