Chapter 12. New High-Temperature Oxide Composite Reinforcement Material: Chrysoberyl

  1. John B. Wachtman Jr
  1. P. J. Whslen,
  2. D. Narasimhan,
  3. C. G. Gasdaska,
  4. E. W. O'Dell and
  5. R. C. Morris

Published Online: 26 MAR 2008

DOI: 10.1002/9780470313848.ch12

Proceedings of the 15th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 12, Issue 9/10

Proceedings of the 15th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 12, Issue 9/10

How to Cite

Whslen, P. J., Narasimhan, D., Gasdaska, C. G., O'Dell, E. W. and Morris, R. C. (1991) New High-Temperature Oxide Composite Reinforcement Material: Chrysoberyl, in Proceedings of the 15th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 12, Issue 9/10 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470313848.ch12

Author Information

  1. Allied-Signal Inc. Research and Technology Center Morristown, NJ 07960

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 1991

ISBN Information

Print ISBN: 9780470375105

Online ISBN: 9780470313848

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Keywords:

  • chrysoberyl;
  • crystals;
  • aluminum;
  • tetrahedral;
  • molybdenum

Summary

The physical and mechanical properties of chrysoberyl, BeAl2O4, have been evaluated to determine its potential as a single crystal reinforcement material for ceramic matrix composites. Chrysoberyl has a lower density, 3.71 g/cm3, and higher stiffness, 469 GPa, than the other leading candidate single crystal oxide materials, sapphire and yttrium aluminum garnet, while having similar thermal properties (thermal expansion and conductivity). The compression creep rates of oriented single crystals of chrysoberyl were measured in a constant load apparatus in the temperature range of 1520°-1820°C. Crystals oriented such that the loading direction was parallel to [001] did not show any detectable creep after 10 h (detectability limit ∼6.5 × 10−9 s+1) at 1820°C and 280 MPa. Sigmoidal type creep was observed for crystals oriented such that the (100) [010] slip system would be activated.