基体对PIP法制备2D C_f/SiC材料抗氧化性能的影响

Effect of the Matrix on the Oxidation Resistance of 2D C_f/SiC Composites by PIP

以3k JC1^#纤维布为增强体，以聚碳硅烷为先驱体，采用先驱体转化工艺制备了2D Cf／SiC复合材料，考察了基体结构对材料抗氧化性能的影响。结果表明，先驱体转化2D Cf／SiC复合材料的抗氧化性能主要与材料基体中的游离碳含量及孔隙率有关，基体中游离碳含量和孔隙率越高，材料的抗氧化性能越差。通过减少基体中的孔隙率和游离碳含量，可以制备抗氧化性能较好的2D Cf／SiC复合材料，在1300℃，马弗炉中氧化20min后，材料的失重率仅为2．2％，弯曲强度和断裂韧性保留率达到83．6％和80．9％。

Two-dimensional carbon fiber cloth reinforced silicon carbide （2D Cf/SiC） composites were fabricated along the route of precursor infiltration and pyrolysis with 3k JC16# carbon fiber cloth as the reinforcement and polycarbosilane （PCS） as precursors. The effects of the matrix microstructure on the oxidation resistance of the composites were investigated. The results showed that the oxidation resistance were related to the contents of free carbon and pores in the matrix. The oxidation resistance of the 2D Cf/SiC composites was improved through reduction of the contents of free carbon and pores in the matrix. After oxidation in a muffle furnace at 1300℃ for 20 minutes, the 2D Cf/SiC composites exhibited good anti-oxidation properties, with the mass loss rate of only 2.2%, and the ratio of flexural strengths and fracture toughness reached 83.6% and 80.9% respectively.