Chapter 11. Micromechanisms of Toughening in a Particulate Reinforced Ceramic Matrix Composite
- John B. Wachtman Jr.
Published Online: 26 MAR 2008
Copyright © 1992 The American Ceramic Society
Proceedings of the 16th Annual Conference on Composites and Advanced Ceramic Materials, Part 1 of 2: Ceramic Engineering and Science Proceedings, Volume 13, Issue 7/8
How to Cite
Brett, R. L. and Bowen, P. (1994) Micromechanisms of Toughening in a Particulate Reinforced Ceramic Matrix Composite, in Proceedings of the 16th Annual Conference on Composites and Advanced Ceramic Materials, Part 1 of 2: Ceramic Engineering and Science Proceedings, Volume 13, Issue 7/8 (ed J. B. Wachtman), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470313954.ch11
- Published Online: 26 MAR 2008
- Published Print: 1 JAN 1994
Print ISBN: 9780470375174
Online ISBN: 9780470313954
The fracture toughness, KICV, of sintered silicon carbide and silicon carbide reinforced with particulate titanium diboride has been evaluated, using chevron notched test pieces in bending, at ambient temperature, 1200°C in air and 1200 and 1600°C in vacuum. There is a significant increase in toughness observed for the composite material at ambient temperature, but no significant increase in toughness above that of the monolithic material is measured both at 1200 and 1600°C. The predominant toughening mechanism in the composite material may therefore be deduced to derive from a favourable distribution of thermal residual stresses, although detailed surface roughness analysis indicates that increased crack deflection occurs at room temperature only. Metallographic observations and fractographic observations (of matched specimen halves) have suggested probable mechanisms of crack extension on a microsmctural scale.