Title: Subcritical crack growth mechanisms in ceramic matrix composites: experimental observations and modelling

Authors: Charles A. Lewinsohn, Charles H Henager Jr, Charles F. Windisch, Edward P. Simonen, Russell H. Jones, Richard G. Hoagland, Akira Kohyama

Addresses: Pacific Northwest National Laboratory, Richiand, WA 99352, USA. ' Pacific Northwest National Laboratory, Richiand, WA 99352, USA. ' Pacific Northwest National Laboratory, Richiand, WA 99352, USA. ' Pacific Northwest National Laboratory, Richiand, WA 99352, USA. ' Pacific Northwest National Laboratory, Richiand, WA 99352, USA. ' Los Alamos National Laboratory, Los Alamos, NM 87545, USA. ' Institute of Advanced Energy, Kyoto University, Uji Campus, Kyoto 611-001, Japan

Abstract: Various experimental techniques were used to identify failure mechanisms that occur under occur in continuous fibre-reinforced ceramic matrix composites containing interphases that are susceptible to oxidation. The conditions under which these mechanisms occur were dictated by environmental conditions and microstructural parameters, such as temperature, oxygen concentration, and interphase thickness. Details of the mechanical state of fibres that bridge matrix cracks, during the operation of each mechanism, were developed to allow the application of models that can predict time-dependent, subcritical crack growth. This paper will present evidence of environmentally induced crack growth and discuss a model for predicting the rate of time-dependent, subcritical crack growth.

Keywords: silicon carbide; ceramic matrix composites; CMC; crack growth; mechanical properties; oxidation; failure mechanisms; fibre reinforcement; interphases; microstructure.

DOI: 10.1504/IJMPT.2001.005411

International Journal of Materials and Product Technology, 2001 Vol.16 No.1/2/3, pp.132 - 138

Published online: 01 Oct 2004 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article