Abstract: An advanced high temperature environmental barrier coating system is disclosed for protecting Si-based ceramics and SiC/SiC ceramic matrix composites (CMCs). This innovation provides a series of environmental barrier coating composition systems to achieve exceptional temperature capability, erosion and calcium-magnesium-aluminosilicate (CMAS) resistance and durability of the environmental barrier coated ceramic turbine engine hot-section components, in harsh turbine engine environments. The environmental barrier coating systems have been demonstrated for 1650° C. temperature capability and help prime-reliant designs.

Abstract: Oxide coatings deposited by plasma spray-physical vapor deposition (PS-PVD) can be processed to be mechanically tough (erosion resistant) and electrically conductive at room temperature. The electrically conductive phase contained within the oxide (MO2) coatings is a metastable suboxide (MO) that has not been formed in significant volume under any other known methods. Content of the electrically conductive phase can be varied in addition to the microstructure, which can be columnar, planar, or a combination of the two depending on the processing conditions. Upon exposing the material to moderate temperatures (>300° C.), the metastable phase is further oxidized (to MO2), and the material becomes insulating, but retains its high toughness and microstructure.