Oxidation Resistance of Double-Layer MoSi₂–Borosilicate Glass Coating on Fiber-Reinforced C/SiO₂ Aerogel Composite

An MoSi₂–borosilicate glass coating with high emissivity and oxidation resistance was prepared on the surface of the fiber-reinforced C/SiO₂ aerogel composite by the slurry method combined with the embedding sintering method under the micro-oxygen atmosphere. The microstructure and phase composition of the coatings with different MoSi₂ contents before and after static oxidation were investigated. This composite material has both excellent radiating properties and outstanding oxidation resistance. The total emissivity values of the as-prepared coatings are all above 0.8450 in the wavelength of 300∼2,500 nm. Meanwhile, the as-prepared M40 coating also has superior thermal endurance after the isothermal oxidation of 1,200°C for 180 min with only 0.27% weight loss, which contributes to the appropriate viscosity of the binder to relieve thermal stress defects. This material has broad application prospects in thermal protection.