超短气体滞留时间制备C/C复合材料及其组织研究  

Microstructure and Fabrication of C/C Composites at Super-short Gas Residence Time

作　　者：和永岗[1] 李克智[1] 魏建锋[1] 郭领军[1] 李贺军[1] 张磊磊[1] 

机构地区：[1]西北工业大学超高温复合材料国防重点实验室炭/炭复合材料研究中心,西安710072

出　　处：《材料工程》2009年第9期33-37,共5页Journal of Materials Engineering

基　　金：国家"973"资助项目(2006CB600908);高等学校学科创新引智计划资助项目(B08040)

摘　　要：以2D针刺炭毡为预制体,天然气为炭源前驱体,无稀释气体,绝对压力为10kPa,沉积温度为1100℃的工艺条件下,通过新型等温化学气相沉积工艺(ICVI),控制气体滞留时间分别为0.01,0.02,0.03s。研究在此超短气体滞留时间下C/C复合材料的致密化过程及密度分布,并采用偏光显微镜(PLM),扫描电子显微镜(SEM)观察其微观组织结构形貌。结果表明:在0.01s的气体滞留时间下,150h的渗透时间内可以制备出表观密度达到1.75g/cm3以上,密度呈现内高外低特点的C/C复合材料,其组织结构为中织构(MT)和高织构(HT)的双层织构,MT只在纤维表面存在且厚度小于2μm,其他均为HT组织。The infiltration of 2D-needle bundle fiber preforms was studied by the novel isothermal chemical vapor infiltration technique （ICVI）, natural gas as the carbon source gas, no diluent gas, at 1100℃ and absolute pressure 10kPa with gas residence time of 0.01, 0.02, 0.03s, respectively. The densification rules were analyzed by densification rate and radial-direction density distribution with different residence time. The textures of samples were observed by polarized light microscopy （PLM） and scanning electron microscopy （SEM）. The results show that 2D preform can be densified from inside to outside at 1100℃ for 150h, with gas residence time 0.01s, the C/C composites have a higher bulk density of 1.75g/cm^3. Simultaneously, the micrographs show that the double-layer textures of the pyrocarbon change from medium-textured （MT） to high-textured （HT）, only lower 2μm thickness MT on the fiber surface.

关 键 词：化学气相渗透 C/C复合材料 滞留时间 致密化 

分 类 号：TB332[一般工业技术—材料科学与工程]