Molten Salt Corrosion of Ceramics

摘要: Molten salt deposits are a major corrodent in heat engines and exchangers. In engine the deposit is sodium sulfate, formed from reaction of ingested sulfur fuel. Conditions for formation discussed. The molten sulfate with silica scale on SiC or Si3N4 best described by acid/base theory oxides. A highly basic will rapidly dissolve this acidic film. Thus knowledge high temperature environment corresponding basicity allow prediction corrosion. overall corrosion deposition, rapid dissolution scale, accelerated oxidation. exhibit extensive pitting and/or grain boundary attack corrosion, which leads to strength reduction. One approach limiting use coatings. Mullite more resistant than SiC, has comparable thermal expansion coefficient thus an ideal coating candidate. Performance mullite coated