themal-barrier-coatings
Thermal barrier coating (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, but 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 multilayered TBC 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.

DVD has been used as a means for depositing 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 realized. Such designs can significantly reduce the cost of building and operating coating deposition systems.

Future use of these multilayer systems in air and industrial gas turbine engines will require improved TBC durability and an increasing resistance to higher temperature and longer exposure to hight temperatures. These requirements are likely to require both advanced top coat materials, due to the lack of phase and thermal stability in traditional zirconia-based systems and advanced bond coat materials with improved oxidation resistance and creep strength. Novel coating materials and structures, both of which are imparting improved properties are being developed through the unique coating composition and morphology control of DVD.

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