Accession Number : ADA336517

Title :   A New Approach Toward the Understanding of Oxidation of Carbon/Carbon Composites

Descriptive Note : Final rept. 1 Jun 92-31 May 95

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF MATERIALS SCIENCE AND ENGINEERING

Personal Author(s) : Thrower, Peter A. ; Radovic, Ljubisa R.

PDF Url : ADA336517

Report Date : 08 MAR 1996

Pagination or Media Count : 7

Abstract : In some recent work, we found that carbon carbon composites made with porous, high- surface-area fibers and liquid matrix precursors were more resistant to oxidation that comparable composites made with non-porous, low-surface-area fibers. The experiments described here were designed in an attempt to assess the relative importance of surface chemistry and porosity of the fibers for the resulting oxidation behavior of the composites. All composites except the high-temperature-related pitch-matrix-precursor composites showed a consistent effect of the surface treatments. Generally, the composites made with fibers given the (an) treatment had superior oxidation resistance. When this is taken in conjunction with the apparent lack of a strong influence from crystallinity, it suggests that chemical adhesion is the dominant mechanism by which the oxidation resistance is improved. Clearly, the large the surface area for adhesion to occur, the more pronounced is the effect.

Descriptors :   *CARBON CARBON COMPOSITES, *OXIDATION RESISTANCE, MICROSTRUCTURE, ADHESION, CARBON FIBERS, POROSITY, SURFACE CHEMISTRY.

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE