Fabrication and testing of corrosion resistant coatings

The susceptibility of SiC and Si{sub 3}N{sub n} to sodium corrosion mandates that corrosion resistant coatings be developed to protect silicon-based turbine engine components. Materials with good corrosion resistance and thermal expansions that nearly match SiC and Si{sub 3}N{sub 4} have been identified. Corrosion testing of hot-pressed pellets of these compounds has identified the most promising materials. Development of chemical vapor deposition system to apply these materials has been initiated. 20 refs., 3 figs.