Chapter 13. Toughening in Ceramic Particulate and Whisker Composites

  1. John B. Wachtman Jr.
  1. Roy W. Rice

Published Online: 26 MAR 2008

DOI: 10.1002/9780470313008.ch13

A Collection of Papers Presented at the 14th Annual Conference on Composites and Advanced Ceramic Materials, Part 1 of 2: Ceramic Engineering and Science Proceedings, Volume 11, Issue 7/8

A Collection of Papers Presented at the 14th Annual Conference on Composites and Advanced Ceramic Materials, Part 1 of 2: Ceramic Engineering and Science Proceedings, Volume 11, Issue 7/8

How to Cite

Rice, R. W. (2008) Toughening in Ceramic Particulate and Whisker Composites, in A Collection of Papers Presented at the 14th Annual Conference on Composites and Advanced Ceramic Materials, Part 1 of 2: Ceramic Engineering and Science Proceedings, Volume 11, Issue 7/8 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470313008.ch13

Author Information

  1. W. R. Grace & Co.-Conn. Columbia, MD 21044

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 1990

ISBN Information

Print ISBN: 9780470374924

Online ISBN: 9780470313008

SEARCH

Keywords:

  • ceramic particulate composites;
  • optimum particle;
  • mechanism;
  • transformation;
  • composition variables

Summary

Analysis of strength-fracture toughness (σ-KIC) of ceramic particulate composites (CPCs), including ZrO2-toughened materials (ZTMs), shows: (1) non-transforming toughened CPCs indicate increasing σ-KIC ratios with decreasing dispersed particulate size and may have an optimum particle size as for ZTMs but probably at finer particle sizes than have been investigated, and (2) both CPCs in general and ZTMs show maxima in σ-KIC ratios at intermediate composite compositions, but generally less in CPCs vs some ZTMs. Evaluation of these two trends for non-transformation toughened CPCs, neither of which are predicted by commonly discussed mechanisms for such composites, suggests (1) crack pinning or alterate mechanisms such as microcrack generation and/or crack branching, and (2) inhibition of flaw generation from machining, respectively. Some whisker composites also indicate intermediate σ/KIC ratio maxima at intermediate composition, and hence, a similar machining-flaw size mechanism as with CPCs. However, the different behavior for whisker composition, e.g., the indicated increase in KIC with increasing whisker diameter, is contrary to proposed mechanisms and behavior of CPCs, but appears consistent with a crack-bridging mechanism.