Thermal barrier coatings (TBC) systems have been incorporated into air and land-based gas turbine engines due to the high near term performance benefits that result from their use. To be successful, these coatings must not only provide thermal insulation, they also remain strongly bonded to the components surface while providing both oxidation and hot corrosion protection of the underlying component. This has resulted in the design of a multi-layered thermal barrier coating system consisting of a bond coat, a thermally grown oxide (TGO) film on top of the bond coat, and a low thermal conductivity top coat.

Directed vapor deposition (DVD) has been used as a means for deposit-ing both the top coat and the bond coat layer. The unique process environment and high efficiency of the process has enabled low cost, moderate volume coaters to be conceived. Such designs can significantly reduce the cost of building and operating coating deposition systems.

Future use of these multi-layer systems in air and industrial gas turbine engines will require improved TBC durability and an increasing resistance to higher temperature and longer time exposures. These requirements are likely to require advanced top coat materials due to the lack of phase and thermal stability in YSZ based systems and bond coats materials that have improved oxidation resistance and creep strength. Novel top coat and bond coat materials and structures having improved properties are being developed using the Directed Vapor Deposition using the unique coating composition and morphology control enabled by the technique.

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