中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 24 No. 10 October 2014 |
（1. Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China;
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
3. Key Laboratory of Ministry of Education for Conveyance and Equipment, College of Mechanical and Electrical Engineering, East China Jiaotong University, Nanchang 330013, China）
Abstract:Unidirectional carbon/carbon (C/C) composites modified with in situ grown carbon nanofibers (CNFs) were prepared by catalysis chemical vapor deposition. The effect of in situ grown CNFs on the flexural properties of the C/C composites was investigated by detailed analyses of destructive process. The results show that there is a sharp increase in the flexural load-displacement curve in the axial direction of the CNF-C/C composites, followed by a serrated yielding phenomenon similar to the plastic materials. The failure mode of the C/C composites modified with in situ grown CNFs is changed from the pull-out of single fiber to the breaking of fiber bundles. The existence of interfacial layer composed by middle-textured pyrocarbon, CNFs and high-textured pyrocarbon can block the crack propagation and change the propagation direction of the main crack, which leads to the higher flexural strength and modulus of C/C composites.
Key words: carbon nanofiber; C/C composites; flexural destruction; crack propagation
