Patent ID: 7364801

Claim:
A turbine component having a polycrystalline superalloy substrate with a surface subjected to oxidation and corrosion, the surface being protected by an environmental coating metallurgically bonded thereto, the environmental coating being predominantly a solid solution phase, the environmental coating consisting of chromium in an amount of about 18 to about 60 weight percent, wherein said amount of chromium, as measured in atomic percent, is higher than the atomic percent of chromium that may be present in the substrate, optionally aluminum in an amount up to about 8 weight percent, optionally up to a total amount of about 5 weight percent of silicon and/or hafnium, optionally up to a total amount of about 2 weight percent of yttrium, lanthanum, cerium, zirconium, magnesium, and rare earth metals, optionally up to a total amount of about 25 weight percent of tungsten, molybdenum, tantalum, rhenium, titanium, niobium, vanadium, and/or platinum group metals, the balance of the environmental coating being incidental impurities and one or more of nickel, cobalt, and iron in amounts to ensure the environmental coating is predominantly the solid solution phase, wherein the environmental coating optionally contains up to 10 volume percent of beta-NiAl intermetallic phase and has an exterior surface protected with a predominantly chromia scale, and wherein the substrate contains residual compressive stresses induced by shot peening the environmental coating.