Chapter 58. The Preparation of Carbon Reinforced Silicon Carbide Composites Using the Isothermal Forced Flow Chemical Vapour Infiltration Technique
- John B. Wachtman Jr.
Published Online: 26 MAR 2008
Copyright © 1993 The American Ceramic Society
Proceedings of the 17th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 14, Issue 9/10
How to Cite
Roman, Y. G., Steijsiger, C., Gerretsen, J. and Metselaai, R. (1993) The Preparation of Carbon Reinforced Silicon Carbide Composites Using the Isothermal Forced Flow Chemical Vapour Infiltration Technique, in Proceedings of the 17th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 14, Issue 9/10 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470314234.ch58
- Published Online: 26 MAR 2008
- Published Print: 1 JAN 1993
Print ISBN: 9780470375273
Online ISBN: 9780470314234
- 3D carbon;
This paper describes the densification of 3D carbon (continuous) fibrous preforms with a SiC matrix using methyltrichlorosilane (MTS) as the precursor in a gas mixture of hydrogen and argon.
The reproducibility in infiltration time, matrix gain and relative composite density as estimated from three FCVI experiments infiltrated at the same process conditions was found to be less than 10%. At a preform temperature of 1273 K and a total outlet pressure of 6.65 kPa, the effect of both the total gas flow rate of the gas mixture and the initial input MTS concentration on the infiltration duration and relative composite density is presented.
Characteristic numbers are presented which describe the SiC deposition profile in a cilindrical pore for both isothermal isobaric CVI (ICVI) and isothermal forced flow CVI (FCVI). Low Damkohler numbers will increase the uniformity of the deposition profile within the pore. Increase of the MTS input concentration will both enhance uniform and rapid infiltration. For ICVI, both rapid and uniform deposition cannot be achieved by changing any other process variable. Whereas in the FCVI case, rapid and uniform deposition can be achieved at high gas velocity.