Abstract: Coating temperature during vapor deposition of a ceramic coating on a substrate in a coating box or enclosure is maintained by means of a heat release cover or lid on the coating enclosure and movable in response to temperature in the coating enclosure exceeding a predetermined value so as to release excess heat from the enclosure to maintain coating temperature within an appropriate range.

Abstract: A gas turbine engine component having a thermal barrier coating is immersed in an inorganic hydroxide bath having a high concentration of alkali or alkaline earth hydroxide with the bath at ambient (atmospheric) pressure and elevated temperature for a time sufficient to effect rapid detachment of the thermal barrier coating for removal from the substrate. The component then optionally can be immersed in a water bath to remove any remaining thermal barrier coating. The thermal barrier coating is removed without detectable damage to the substrate or any bondcoat present thereon.

Abstract: A non-destructive measurement method for determining residual stress proximate an intermediate layer in a multilayer thermal barrier coating system by directing a laser beam through an outer ceramic thermal insulating layer with the laser beam illuminating a ceramic-bearing intermediate layer in a manner to cause species present in the intermediate layer to fluoresce, measuring the frequency of the light or photons emitted by the fluroescing species, and comparing the measured frequency shift of the intermediate ceramic layer to the frequency shift determined on like ceramic material under controlled stress states to determine a representation of relative residual stress in the measured coating. The invention can be used to assess integrity or quality control of as-manufactured TBC coatings or to assess remaining coating service life of engine-run TBC coated components during an inspection or repair procedure.

Abstract: A thermal barrier protected nickel based or cobalt based superalloy component for use in a gas turbine engine includes a thermal barrier coating system having a multi-layered structure. The first bondcoat layer of the thermal barrier coating system comprises a chemical vapor deposited, platinum modified diffusion aluminide layer on the superalloy component (substrate). The diffusion aluminide layer includes an inner diffusion zone proximate the substrate and an outer layer region comprising a platinum modified (platinum-bearing) intermediate phase of aluminum and at least one of nickel and cobalt depending on the superalloy composition. The intermediate phase is a non-ordered solid solution having a range of compositions and is free of other phase constituents.

Abstract: A thermal barrier protected nickel based or cobalt based superalloy component for use in a gas turbine engine includes a thermal barrier coating system having a multi-layered structure. The first bondcoat layer of the thermal barrier coating system comprises a chemical vapor deposited, platinum modified diffusion aluminide layer on the superalloy component (substrate). The diffusion aluminide layer includes an inner diffusion zone proximate the substrate and an outer layer region comprising a platinum modified (platinum-bearing) intermediate phase of aluminum and at least one of nickel and cobalt depending on the superalloy composition. The intermediate phase is a non-ordered solid solution having a range of compositions and is free of other phase constituents.

Abstract: Sputtering techniques are utilized to form an aluminum rich diffusion coating on the surface of a superalloy substrate. The coating contains additions of oxygen active elements, such as yttrium, and the coating has an outward diffusion aluminide microstructure obtained by carrying the sputtering process out at temperatures in the range of about 1,010.degree.-1,150.degree. C.

Abstract: Compositions and articles are described which have particular utility in gas turbine engine parts and which can be used at temperatures up to and in excess of 2,000.degree. F. without the usual protective coatings. Compositions are described which can be formed into single crystal articles which are alumina formers upon exposure to oxidation and in which develop an adherent spall resistant alumina scale during oxidation. The adherence and spall resistance of the alumina surface scale results from the presence of a small but critical quantity of zirconium.