Mechanical Properties of Low‐Density SiC‐Coated Carbon‐Bonded Carbon Fiber Composites

Carbon‐bonded carbon fiber (CBCF) composites are currently used for high‐temperature thermal insulation, but they can only be used under protective atmosphere or vacuum due to their limited oxidation resistance. High temperature stability may be improved by the addition of a protective coating of silicon carbide. The effect of this coating on key mechanical properties of CBCF composites, namely flexural and compressive strength, modulus, and fracture toughness, is reported here. The fracture toughness of coated and uncoated materials was also determined at elevated temperatures. A significant increase of all mechanical properties was found when the protective coating was present.