Process for obtaining surface coatings on silicon nitride ceramic parts and components.

摘要

Process for obtaining surface coatings on silicon nitride ceramic parts and components.; Process for obtaining surface coatings of silicon nitride (Si {3} N {4}) on parts and ceramic components by impregnating the surfaces of the ceramic with powder suspensions silicon particle size preferably less than 200 mum. The thickness of the coatings depends on the soaking time, the properties of the slip and ceramics. The subsequent nitriding of the coating by heat treatment at temperatures between 1300 ° C and 1500 ° C in atmospheres of N {2}, leading to a continuous coating of SI_ {3} {4} N. Stability and chemical compatibility between SI_ {3} N {4}) and the molten silicon enables application in silicon metallurgy, like making crucibles for melting silicon or for receiving molten silicon, tube and channels for transport, or different components for further purification.