Ceramic matrix composites (CMCs) are being developed to take advantage of the high-temperature properties of ceramics while overcoming the low fracture toughness of monolithic ceramics. Toughening mechanisms, such as matrix cracking, crack deflection, interface debonding, crack-wake bridging and fiber pullout, are being incorporated in CMCs to reduce the tendency for catastrophic failure found in monolithic ceramics. Ceramics reinforced with particulate, whiskers and continuous fibers exhibit varying aspects of these toughening mechanisms; however, reinforcement with continuous fibers offers the greatest improvements in toughness. Composites with carbide, oxide, glass and carbon matrices are being utilized in the development of CMCs. In the case of carbide, oxide and glass matrix CMCs, the matrix exhibits excellent high-temperature corrosion resistance so that a goal of the composite development is to not detract from this pre-existing property. This is not the case for carbon matrix composites which frequently need coatings to provide adequate corrosion protection. The purpose of this chapter is to review the database and understanding of corrosion behavior of CMCs with the intent that this information will be useful in the development of materials with improved performance and reliability.
Revised: January 17, 2011 |
Published: November 12, 2001
Citation
Jones R.H., C.H. Henager, C.A. Lewinsohn, and C.F. Windisch. 2001.Ceramic Matrix Composites. In Environmental Effects on Engineered Materials, edited by Russell H. Jones. 391-418. New York, New York:Marcel Dekker.PNNL-SA-32809.