乙醇热解制备C/C复合材料探索研究

Carbon/carbon composites prepared by an ethanol pyrolysis

以可再生的资源无水乙醇为前驱体,在负压条件下,沉积温度为900℃～1200℃,采用压力梯度CVI工艺制备C/C复合材料。考察了沉积时间与密度的变化规律,采用偏光显微镜和扫描电镜观察了材料的组织结构和断口形貌,利用三点弯曲测定了材料的弯曲强度。结果表明:采用乙醇为前驱体,可大幅度提高致密化效率,96h制备出密度为1.47g/cm3的C/C复合材料;易于获得高织构的组织,制备试样的热解炭组织以粗糙层为主,断裂方式为假塑性断裂。乙醇是一种很有应用前景的制备C/C复合材料的前驱体。

Ethanol, which is a renewable resource, was used as a precursor to prepare carbon/carbon （C/C） composites by chemical vapor infiltration （CVI）, and the relationship between density and infiltration time was investigated. The flexural strength was determined by a three-point bend test. The microstructure and fracture- surface morphology of the composites were observed by polarized light microscopy and scanning electron micros- copy respectively. Results show that the bulk density reaches 1.47 g/cm3 for a 96 h densification, a significant improvement in densification efficiency compared with other precursors. A high-textured carbon matrix, consisting of rough laminar pyrocarbon, can be easily obtained. The C/C composites exhibit a pseudo-plastic failure behavior. Ethanol is a new promising precursor for the densification of C/C composites.