Chapter 26. Rb β-Alumina as an Interface Coating in Oxide CMCs

  1. John B. Wachtman Jr.
  1. S. Sambasivan1,
  2. J. A. Morris1 and
  3. W. T. Petuskey2

Published Online: 28 MAR 2008

DOI: 10.1002/9780470314876.ch26

Proceedings of the 20th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures - B: Ceramic Engineering and Science Proceedings, Volume 17, Issue 4

Proceedings of the 20th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures - B: Ceramic Engineering and Science Proceedings, Volume 17, Issue 4

How to Cite

Sambasivan, S., Morris, J. A. and Petuskey, W. T. (2008) Rb β-Alumina as an Interface Coating in Oxide CMCs, in Proceedings of the 20th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures - B: Ceramic Engineering and Science Proceedings, Volume 17, Issue 4 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470314876.ch26

Author Information

  1. 1

    BIRL, Northwestern University Evanston IL-60201

  2. 2

    Department of Chemistry Arizona State University Tempe, AZ-85287

Publication History

  1. Published Online: 28 MAR 2008
  2. Published Print: 1 JAN 1996

ISBN Information

Print ISBN: 9780470375433

Online ISBN: 9780470314876

SEARCH

Keywords:

  • sapphire monofilaments;
  • interface coating;
  • potential interface coating;
  • fiber-mabix intafaece;
  • alumina matrix

Summary

Rubidium stabilized α-alumina was selected as a potential interface coating material for high temperature ceramic matrix composites. The coatings were developed by MOCVD on sapphire monofilaments which were then hot pressed in an alumina matrix for testing of coating's thermal, chemical, and morphological stability and interfacial properties. While earlier studies have shown Rb β-alumina to be stable up to 1600°C, this study showed loss of rubidia from surface of bulk specimens above 120°C. The coating appears to be chemically stable and compatible with alumina in the hot pressed specimen. Indentation tests performed on the hot pressed specimens show crack deflection at the fiber-matrix interface whereas push out tests showed no debonding of the fiber from the matrix.