Oxidation behavior of 2D C/SiC composite modified by SiB4 particles in inter-bundle pores

In order to understand the oxidation resistance of a 2D C/SiC composite protected with self-healing filler in the inter-bundle pores, SiB4 particles as the filler were infiltrated into the inter-bundle pores of 2D C/SiC composite by slurry infiltration process. The SiB4 particles were combined with SiC during the chemical vapor deposition (CVD) SiC coating process. Isothermal oxidation tests of the as-received modified composite were carried out in air at temperatures ranging from 500 to 1000 °C. SEM and EDS results showed that all the open inter-bundle pores of the C/SiC composite can be filled with SiB4 particles. The SiB4 filler can hinder the inwards diffusion of oxygen in air, and protect the carbon fibres and carbon interphase from oxidation. As a result, the modified composite lost weight slowly, and showed no obvious decrease in flexural strength at the temperatures of 500–900 °C for an oxidation time of 10 h.