Oxidation and thermal degradation resistance of silicon carbide coated low density carbon–carbon composite

Abstract

The material investigated in this study is a prototype material, where a low density and highly porous carbon–carbon composite, termed carbon bonded carbon fibre (CBCF), has been given a protective coating of silicon carbide using chemical vapour deposition. The aim of the current study was to gauge the effectiveness of the silicon carbide coating in protecting the CBCF materials from degradation within an oxidising atmosphere. Avenues of investigation included assessing the behaviour of the materials when heated to elevated temperatures within an oxidising environment (using thermogravimetric analysis and bulk oxidation tests) and also evaluating the residual strength of the composites after subjection to thermal shock/cycling. It has been found that the performance of the CBCF material in oxidising conditions has improved with the incorporation of the silicon carbide coating and also that the coated material is resilient against thermal shock/cycling.