Chapter 21. Mechanics of Crack-Tip Damage During Static and Cyclic Crack Growth in Ceramic Composites at Elevated Temperatures

  1. John B. Wachtman Jr.
  1. S. Suresh and
  2. L. X. Han

Published Online: 28 MAR 2008

DOI: 10.1002/9780470310588.ch21

A Collection of Papers Presented at the 13th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 10, Issue 9/10

A Collection of Papers Presented at the 13th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 10, Issue 9/10

How to Cite

Suresh, S. and Han, L. X. (1989) Mechanics of Crack-Tip Damage During Static and Cyclic Crack Growth in Ceramic Composites at Elevated Temperatures, in A Collection of Papers Presented at the 13th Annual Conference on Composites and Advanced Ceramic Materials, Part 2 of 2: Ceramic Engineering and Science Proceedings, Volume 10, Issue 9/10 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470310588.ch21

Author Information

  1. Division of Engineering Brown University Providence, RI 02912

Publication History

  1. Published Online: 28 MAR 2008
  2. Published Print: 1 JAN 1989

ISBN Information

Print ISBN: 9780470374870

Online ISBN: 9780470310588

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Keywords:

  • silicon nitride;
  • ceramic matrix;
  • fractography;
  • microstructure;
  • morphology

Summary

This presentation examines the mechanisms of high temperature crack growth under static and cyclic tensile loads of an Al2O3-SiC whisker composite in the temperature range 1300°–1500°C. Crack growth behavior under static and cyclic bads was characterized by da/dt vs K, and da/dN vs K plots, respectively. Detailed transmission electron microscopy of the crack-tip region, in conjunction with optical and scanning electron microscopy, are conducted to deduce the origin of permanent damage under creep conditions. Particular attention is focused on stress amplitude and mean stress effects, interfacial reactions, the flow of glassy phase, and microcrack growth along interfaces and grain boundaries. The failure behavior of reinforced ceramics is compared and contrasted with the creep crack growth characteristics of unreinforced alumina ceramic. Theoretical and experimental results of crack growth in Al2O3-SiC and Si3N4-Sic composites under cyclic compressive stresses at ambient and elevated temperatures are also discussed.