Conversion coatings on silicon carbide

摘要

A pack cementation method is described for producing conversion coatings on a ceramic. In particular, silicon carbide is coated with Cr2O3-forming compounds for improved sulfidation and ash-deposit resistance. The method is applicable to continuous fiber ceramic composites or a monolithic substrate. The conversion coatings are multilayered coating systems with the coating morphologies expressed as follows: Cr23C6/Cr7C3/Cr7C3-Cr3Si/Cr5Si3Cx/Substrate Cr/Cr3Si/Cr5Si3Cx/SiC Substrate