Si-O-C界面对C/Si-C-N复合材料性能的影响

采用CVI工艺制备基体、PIP方法制备界面,成功制备出了具有Si-O-C界面层的碳纤维增强Si-C-N陶瓷基复合材料(C/Si-O-C/Si-C-N),研究了Si-O-C界面层对C/Si-C-N复合材料力学性能、抗氧化性能和热膨胀性能的影响。结果表明,C/Si-C-N陶瓷基复合材料在采用Si-O-C界面层后,相对于采用热解碳界面的同类复合材料,其抗氧化性能明显提高,强度则基本相当,在实验温度区间内,平均热膨胀系数略有升高。

Influence of Si-O-C Interlayer on the Properties of C/Si-C-N Composites

The carbon fiber reinforced Si-C-N ceramic matrix composite with a Si-O-C interlayer(C/Si-O-C/Si-C-N) was fabricated with the matrix fabricated by CVI and the interphase fabricated by PIP. The influence of Si-O-C interlayer on the mechanical properties, oxidation resistance and thermal expansion properties of the composites was investigated. The results indicate that compared to the C/Si-C-N with a pro-carbon interlayer(C/PyC/Si-C-N), the oxidation resistance of C/Si-C-N composite with a Si-O-C interlayer (C/Si-O-C/Si-C-N) was improved. The strength of C/Si-O-C/Si-C-N can compare with that of C/PyC/Si-C-N. The ave-rage coefficient of thermal expansion of C/Si-O-C/Si-C-N was higher than that of C/PyC/Si-C-N throughout the experimental tempe-rature range.