Synthesis of highly tailored ceramic matrix composites by pressure-pulsed CVI

Pressure-pulsed chemical vapor infiltration (P-CVI) is a new processing tec hnique to produce ceramic matrix composites (CMCs) (C/C, C/SiC and SiC/SiC) from gaseous precursors with highly tailored interphases and matrices. P-C VI can be used to control the microtexture of pyrocarbon deposited from hyd rocarbon in a porous body. It is also used to form (PyC-SiC)(n) or (BN-SiC) (n) interphases with elementary layer thickness of a few nanometers. Finall y, P-CVI is an efficient way to produce self-healing matrices comprising me chanical fuse layers (PyC or BN) and glass-former layers (B13C2 or/and SiC) . The resulting model or real composites display an oxidation resistance, i n air at 600-700 degreesC and under load, which is improved by two orders o f magnitude. (C) 2001 Elsevier Science B.V. All rights reserved.