Chapter 7. Flexural Creep and Creep-Rupture Behavior of SiC/BN Dual Coated Nicalon Fiber Reinforced Glass-Ceramic Matrix Composites

  1. John B. Wachtman Jr.
  1. Ellen Y. Sun1,
  2. Steven R. Nutt1 and
  3. John J. Brennan2

Published Online: 28 MAR 2008

DOI: 10.1002/9780470314500.ch7

Proceedings of the 18th Annual Conference on Composites and Advanced Ceramic Materials - A: Ceramic Engineering and Science Proceedings, Volume 15, Issue 4

Proceedings of the 18th Annual Conference on Composites and Advanced Ceramic Materials - A: Ceramic Engineering and Science Proceedings, Volume 15, Issue 4

How to Cite

Sun, E. Y., Nutt, S. R. and Brennan, J. J. (1994) Flexural Creep and Creep-Rupture Behavior of SiC/BN Dual Coated Nicalon Fiber Reinforced Glass-Ceramic Matrix Composites, in Proceedings of the 18th Annual Conference on Composites and Advanced Ceramic Materials - A: Ceramic Engineering and Science Proceedings, Volume 15, Issue 4 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470314500.ch7

Author Information

  1. 1

    Division of Engineering, Brown University, Providence, RI02912

  2. 2

    United Technologies Research Center, East Hartford, CT 06108

Publication History

  1. Published Online: 28 MAR 2008
  2. Published Print: 1 JAN 1994

ISBN Information

Print ISBN: 9780470375327

Online ISBN: 9780470314500

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Keywords:

  • flexural;
  • creep;
  • variable differential;
  • creep-strain;
  • stressconcentration

Summary

An advanced structural composite was produced by incorporating coated Nicalon fibers into a barium magnesium aluminosilicate (BMAS) glass-ceramic matrix. The fibers were coated with a dual layer of SiC/BN by CVD. The flexural creep and creep-rupture behavior of the composites was investigated. Flexural creep experiments were conducted at 1000 — 1200°C in air under applied stresses of 100 — 670MPa using three-point and four-point bending fixtures. The constant creep rates were low (∼10E-9 s−1) and beyond our ability to accurately measure at temperatures below 1130°C. Large creep-strain recovery (∼90%) was observed upon unloading. At stress levels close to the composite ultimate failure stress, hinges formed under the loading pins and creep-rupture occurred subsequently.