The effect of hole defects on the oxidation behaviour of two-dimensional C/SiC composites

Oxidation behaviour of two-dimensional (2D) C/SiC composites with 0, 1 and 2 mm average diameter holes has been investigated in air at 700 °C. Oxidation tests, mechanical tests, microstructural characterization and computed tomography (CT) were performed to find the effect of hole defects on the oxidation behaviour of C/SiC composites. The experimental results pointed out that the thermal exposure area (TEA) ratio and oxidation time were two key affecting factors on the oxidation behaviour. Weight loss was found to accelerate at oxidation durations higher than 1 h, thereafter residual tensile strength also dropped. A TEA ratio of 16% was found as critical in severely downgrading the residual tensile strength and significantly weakening the oxidation resistance behaviour for C/SiC composites contain hole defects.