Abstract: A method for applying a chromium containing coating to an underlying metal substrate where the metal substrate has an overlaying platinum-containing layer, as well as a corrosion resistant coated article thereof. A chromium-containing layer is deposited on the platinum-containing layer with an aluminide diffusion layer being deposited on the chromium-containing layer, the aluminide diffusion layer having an inner diffusion layer adjacent the chromium-containing layer and an outer additive layer adjacent to the inner diffusion layer. The chromium-containing layer is deposited by a deposition technique that permits chromium in the chromium-containing layer to more readily diffuse into a subsequently deposited aluminde diffusion coating layer. The chromium-containing and aluminide diffusion layers are then treated to cause chromium from the chromium-containing layer to diffuse into the outer additive layer in an amount of at least about 8%. The resulting coated article is resistant to corrosion.

Abstract: Thermal barrier coating (TBC) and a method of depositing a TBC having a modulated columnar microstructure that exhibits increased impact resistance. The TBC is deposited to have a columnar microstructure in which columns extend from a substrate surface. The columns having inner regions contacting the surface, outer regions near an outermost surface of the TBC, and interior regions therebetween. The inner regions of the columns are substantially normal to the substrate surface and at least one of the interior and outer regions of the columns are nonaligned with its respective inner regions, so that the columns of the columnar microstructure are continuous but modulated between the inner and outer regions to reduce tensile stresses within the columns resulting from particle impact.

Abstract: A method for selectively removing an aluminide coating from at least one surface of a metal-based substrate by: (a) contacting the surface of the substrate with at least one stripping composition comprising nitric acid at a temperature less than about 20° C. to degrade the coating without damaging the substrate; and (b) removing the degraded coating without damaging the substrate. Also disclosed is a method for replacing a worn or damaged aluminide coating on at least one surface of a metal-based substrate by selectively removing the coating using the above steps, and then applying a new aluminide coating to the surface of the substrate. Turbine engine parts, such as high-pressure turbine blades, treated using the above methods are also disclosed.

Abstract: A method for selectively removing an aluminide coating from at least one surface of a metal-based substrate by: (a) contacting the surface of the substrate with at least one stripping composition comprising nitric acid at a temperature less than about 20° C. to degrade the coating without damaging the substrate; and (b) removing the degraded coating without damaging the substrate. Also disclosed is a method for replacing a worn or damaged aluminide coating on at least one surface of a metal-based substrate by selectively removing the coating using the above steps, and then applying a new aluminide coating to the surface of the substrate. Turbine engine parts, such as high-pressure turbine blades, treated using the above methods are also disclosed.