Study on the Electric Properties of Carbon Fibers and its Application for the Preparation of Carbon/Carbon Composites

Abstract:

Acetylene (C₂H₂) was used as carbon source gas, nitrogen (N₂) as dilution gas. The electric properties of carbon fibers was briefly discussed by energizing the carbon fibers in vacuum condition which were applied for the preparation of carbon/carbon composites by the method of chemical vapor deposition. The deposition mechanism and microstructure of pyrolytic carbons in carbon fibers under different deposition crafts were also discussed. Results indicate that the greater the initial voltage, the higher the temperature, we can change the deposition temperature by changing the initial voltage according to the relationship between the brightness and the surface temperature of carbon fibers. The surface of carbon fibers will be etched in the process of electrifying which would make the pyrolytic carbons preferred deposition on the etching point which became the growth center in the early deposition process. The pyrolytic carbons deposited with a spherical microcrystalline structure under the gas flow of C₃H₆/N₂=2:3, When the rate of gas flow is C₃H₆/N₂=1:2, The pyrolytic carbons deposited with a spherical microcrystalline structure after deposited for 0.5h, but after deposited for 1h, the deposition of large patches of molecular is dominant which lead to that: from a macro perspective, the pyrolytic carbons were a layered structure, From a microscopic perspective, they were a spherical microcrystalline structure with different size.

• Periodical: Materials Science Forum (Volumes 809-810)
• Pages: 707-710
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.809-810.707
• Online since: December 2014
• Authors: Xian Feng Xu, Ling Zhi Chai*, Hui Li, Ling Sheng Zeng
• Keywords: Electric Properties, Layered Structure, Pyrolytic Carbons, Spherical Microcrystalline Structure

References

[1] J.G. Zhao, G.C. chen and H.Q. Wang, et al. The research progress of carbon/carbon composites by the method of chemical vapor deposition [J]. Modern chemical industry, 2006, (S2): 68-71.

[2] Y.Q. Wang, R.Y. Luo. The research status of densification process of carbon/carbon composites [J]. Carbon technology, 2011, (02): 24-29. (In Chinese).

[3] F. He. The electric properties of carbon fibers and its applications[J]. New chemical materials, 2005, 33(06): 7-8. (In Chinese).

[4] X.M. Huang, T. Ji and J. Yu. The design and development of carbon fiber electric heating cloth [J]. Industrial textiles, 2009, (06): 13-16.

[5] C.H. Yan. The study on the properties of carbon fibers[J]. Guang xi textile science and technology, 2009, 38(05): 4-6.

[6] R.Y. Luo. Fabrication of carbon/carbon composites by an electrified perform heating CVI method[J]. Carbon, 2002, (40): 1957-(1963).

DOI: 10.1016/s0008-6223(02)00027-1

[7] L.J. Xue, J.M. Su and Z.C. Xiao. The research and development of the densification about C/C composites by CVI[J]. Carbon technology, 2008, (04): 49. (In Chinese).

[8] Q. Li, R.Y. Luo and Y.H. Cheng. The deposition mechanism and microstructure of pyrolytic carbon by chemical vapor deposition [J]. Carbon technology, 2003, (04): 2-6. (In Chinese).

[9] L.N. Wang, C. Lang and X.D. Wang, et al. The study on the resistance temperature characteristics of carbon fibers under a laboratory temperature [J]. University physics experiment, 2001, 14(02): 33-35. (In Chinese).