Chapter 13. Toughening in Ceramic Particulate and Whisker Composites
- John B. Wachtman Jr.
Published Online: 26 MAR 2008
Copyright © 1990 The American Ceramic Society, Inc.
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
- Published Online: 26 MAR 2008
- Published Print: 1 JAN 1990
Print ISBN: 9780470374924
Online ISBN: 9780470313008
- ceramic particulate composites;
- optimum particle;
- composition variables
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.