Chapter 49. High-Temperature Compressive Deformation of Si3N4/BN Fibrous Monoliths

  1. Ersan Ustundag and
  2. Gary Fischman
  1. J. L. Routbort1,
  2. K. C. Goretta1,
  3. E. T. Park1,
  4. D. Singh1,
  5. J. Finch2,
  6. J. Staehler2,
  7. L. Zawada2 and
  8. G. E. Hilmas3

Published Online: 26 MAR 2008

DOI: 10.1002/9780470294567.ch49

23rd Annual Conference on Composites, Advanced Ceramics, Materials, and Structures : A: Ceramic Engineering and Science Proceedings, Volume 20, Issue 3

23rd Annual Conference on Composites, Advanced Ceramics, Materials, and Structures : A: Ceramic Engineering and Science Proceedings, Volume 20, Issue 3

How to Cite

Routbort, J. L., Goretta, K. C., Park, E. T., Singh, D., Finch, J., Staehler, J., Zawada, L. and Hilmas, G. E. (1999) High-Temperature Compressive Deformation of Si3N4/BN Fibrous Monoliths, in 23rd Annual Conference on Composites, Advanced Ceramics, Materials, and Structures : A: Ceramic Engineering and Science Proceedings, Volume 20, Issue 3 (eds E. Ustundag and G. Fischman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470294567.ch49

Author Information

  1. 1

    Energy Technology Division Argonne National Laboratory, Argonne, IL 60439

  2. 2

    Materials and Manufacturing Directorate AFRL/MLLN, Wright-Patterson Air Force Base, OH 45433

  3. 3

    Advanced Ceramics Research Tucson, AZ 85706

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 1999

ISBN Information

Print ISBN: 9780470375631

Online ISBN: 9780470294567

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Keywords:

  • monolithic;
  • unidirectional;
  • plasticity;
  • ceramic;
  • extrusion

Summary

Fibrous monolithic Si3N4/BN (≈85 vol.% Si3N4/15 vol.% BN) and monolithic Si3N4 ceramics were compressed at a nearly constant strain rate (ϵ) at 1200–1400°C in N2. The ϵ range was ≈1 × 10−6 to 5 × 10−6 s−1; the stress (σ) range was 37–202 MPa. The Si3N4 and the unidirectional fibrous monoliths that were oriented with the long axis of the Si3N4 cells parallel to the compression direction exhibited plasticity at 1300 and 1400°C, with ϵ ∞ σ. A 0/90° cross-ply Si3N4/BN laminate also exhibited significant plasticity, but it was weaker than the above-mentioned ceramics. The unidirectional fibrous monoliths that were compressed perpendicular to the cell direction fractured at ≈50 MPa in all tests. A ±45° laminate tested at 1300°C fractured at a stress of ≈40 MPa. Low fracture stress correlated with shear through BN layers.