Chapter 10. Super-Tough Silicon Nitride with R-Curve Behavior
- John B. Wachtman Jr.
Published Online: 26 MAR 2008
Copyright © 1989 The American Ceramic Society, Inc.
A Collection of Papers Presented at the 13th Annual Conference on Composites and Advanced Ceramic Materials, Part 1 of 2: Ceramic Engineering and Science Proceedings, Volume 10, Issue 7/8
How to Cite
Li, C.-W. and Yamanis, J. (2008) Super-Tough Silicon Nitride with R-Curve Behavior, in A Collection of Papers Presented at the 13th Annual Conference on Composites and Advanced Ceramic Materials, Part 1 of 2: Ceramic Engineering and Science Proceedings, Volume 10, Issue 7/8 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470310557.ch10
- Published Online: 26 MAR 2008
- Published Print: 1 JAN 1989
Print ISBN: 9780470374863
Online ISBN: 9780470310557
- chemical vapor infiltration;
- silicon nitride ceramics;
- fracture toughness;
- crack growth resistance
Silicon nitride with a fracture toughness of 10.6 ± 0.5 MPa · m1/2 has been developed. This tough, nontransforming ceramic exhibits pronounced R-curve behavior. Double cantilever beam (DCB) and indentation/strength measurements were used to characterize the R-curve, and good agreement between the two methods was obtained. The high toughness and R-curve behavior of this silicon nitride material is attributed to extensive crack deflection and crack bridging phenomena arising from its unique microstructure. As a result of R-curve behavior, the material exhibits flaw tolerance and is, therefore, characterized by a high Weibull modulus. Furthermore, this ceramic is more damage tolerant than silicon nitrides with flat crack growth resistance.