Structural characterisation of SiC/SiCf composites exposed to chemical interaction with Be at high temperature

Fibre-reinforced SiC composites are candidate materials for application in nuclear fusion technology as structural materials due to their low activation and high performance properties. We studied the chemical compatibility between SiC/SiCf composites and Be under isothermal conditions at 800 °C. Two types of SiC/SiCf composites were used, one of them with a surface CVD coating of SiC powder. Results show that, after the chemical compatibility tests, the surface of uncoated samples is heavily oxidised with C surface depletion and Be in-diffusion. For the coated samples the chemical reactions are not so severe. Experiments indicate the presence of Si and Be2C as reaction products in the surface of both samples.