Chapter 16. Chemical Vapor Deposition of Oxidation Resistant HfB2 + SiC Composite Coatings
- John B. Wachtman Jr
Published Online: 26 MAR 2008
Copyright © 1988 The American Ceramics Society, Inc.
12th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 9, Issue 9/10
How to Cite
Lackey, W. J., Smith, A. W. and Twait, D. J. (1988) Chemical Vapor Deposition of Oxidation Resistant HfB2 + SiC Composite Coatings, in 12th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 9, Issue 9/10 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470310502.ch16
- Published Online: 26 MAR 2008
- Published Print: 1 JAN 1988
Print ISBN: 9780470374818
Online ISBN: 9780470310502
- carbon-carbon composites
Prior testing has repeatedly shown a HfB2 + SiC composite to have oxidation resistance superior to that of HfB2 or SiC. The majority of the prior work has relied on hot pressing or hipping for fabrication. Attempts to prepare the material by chemical vapor deposition have been unsuccessful. We have recently performed computerized thermodynamic free energy minimization calculations which predict reagent concentrations for the HfCl2-CH3-SiCl3-BCl3-H2 system which should result in the codeposition of the HfB2 + SiC composite at 1200–1500 K. Coatings of HfB2 + SiC offer potential for oxidation protection of graphite and carbon-carbon composites.