CVI-RMI法制备C/SiC复合材料的微观结构与弯曲性能  

Microstructure and flexural properties of C/SiC composites by CVI-RMI method

作　　者：肖鹏[1] 谢建伟[1] 熊翔[1] 闫志巧[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2007年第3期381-385,共5页Journal of Central South University:Science and Technology

基　　金：湖南省杰出青年科学基金资助项目(06JJ10007);国家高技术研究发展计划资助项目(2006AA03Z560)

摘　　要：以T700炭纤维准三维编织针刺整体毡为预制体,在炭纤维表面CVI预沉积热解炭涂层,利用化学气相渗透-反应熔体浸渗法(CVI-RMI)制备C/SiC复合材料,观察材料的微观形貌,并探讨界面对弯曲性能的影响。研究结果表明:利用CVI-RMI联合工艺制备的C/SiC复合材料致密度高,开孔率较小(10%),基体分布均匀;材料弯曲强度达133 MPa,呈逐层破坏机制,表现出良好的假塑性;热解炭涂层与CVI-SiC基体减少了RMI工艺过程对炭纤维的损伤,且热解炭涂层调节了炭纤维与基体之间的界面结合状况,有利于纤维的拔出。Pyrolytic carbon coating and successive SiC matrix were respectively prepared by chemical vapor infiltration （CVI） in T700 kind integer felt. The subsequent reactive melt infiltration （RMI） method was adopted to densify it further and C/SiC composites were successively prepared. The microstructure and effect of interface on flexural properties were thoroughly investigated. The results show that C/SiC composites fabricated by CVI-RMI methods have high density and low porosity（10%）, in which CVI-SiC and RMI-SiC distribute uniformly. The flexural strength of the composites is 133 MPa. The composites are damaged layer by layer with good pseudo-plasticity. C fibers are damaged lightly because of pyrolytic carbon coating and CVI-SiC. Pyrolytic carbon coating moderates the interface strength between C fibers and SiC, which is beneficial to the pulling out of C fibers.

关 键 词：C/SIC复合材料 微观结构 化学气相渗透法 反应熔体浸渗法 弯曲性能 

分 类 号：TB332[一般工业技术—材料科学与工程]