Abstract: A method for forming a nickel aluminide based coating on a metallic substrate includes providing a first source for providing a significant portion of the aluminum content for a coating precursor and a separate nickel alloy source for providing substantially all the nickel and additional alloying elements for the coating precursor. Cathodic arc (ion plasma) deposition techniques may be utilized to provide the coating precursor on a metallic substrate. The coating precursor may be provided in discrete layers, or from a co-deposition process. Subsequent processing or heat treatment forms the nickel aluminide based coating from the coating precursor.

Abstract: A protective coating for use on a silicon-containing substrate, and deposition methods therefor. The coating has a strontium-aluminosilicate (SAS) composition that is less susceptible to degradation by volatilization and in corrosive environments as a result of having at least an outer surface region that consists essentially of one or more stoichiometric crystalline phases of SAS and is substantially free of a nonstoichiometric second crystalline phase of SAS that contains a substoichiometric amount of silica. The coating can be produced by carrying out deposition and heat treatment steps that result in the entire coating or just the outer surface region of the coating consisting essentially of the stoichiometric celsian phase.

Abstract: A coated article suitable for use at elevated temperature includes a metal substrate and a coating on the substrate. The coating includes a corrosion resistant particulate component having an average coefficient of thermal expansion (CTE) greater than alumina at 1200° F. (649° C.) dispersed in a binder matrix. An aspect ratio of at least a portion of the corrosion resistant particulate component is greater than about 2:1. The binder matrix includes a silicon-containing material and/or a phosphate-containing material.

Abstract: Method comprising providing a coating precursor composition including a corrosion resistant particulate component having an average coefficient of thermal expansion (CTE) greater than alumina at 1200° F. (649° C.) dispersed in a binder matrix, wherein an aspect ratio of at least a portion of the corrosion resistant particulate component is greater than about 2:1, and wherein the binder matrix includes at least one member of the group consisting of a silicon-containing material and a phosphate-containing material; providing the coating precursor composition on at least a portion of a metal substrate, and; curing the coating precursor composition to provide a corrosion-resistant coating on at least the portion of the metal substrate.

Abstract: A method for producing a thermal barrier coating/environmental barrier coating system on a silicon containing material substrate includes applying an environmental barrier coating (EBC) over the silicon containing material substrate; and applying a thermal barrier coating (TBC) over the EBC. The thermal barrier coating includes a compound having a primary constituent portion and a stabilizer portion stabilizing said primary constituent. The primary constituent portion of the thermal barrier coating includes hafnia present in an amount of at least about 5 mol % of the primary constituent and the stabilizer portion of said thermal barrier coating includes at least one metal oxide comprised of cations with a +2 or +3 valence present in the amount of about 10 to about 40 mol % of the thermal barrier coating.

Abstract: A superalloy composition comprising, in weight percent: about 6.2-6.6 Al, about 6.5-7.0 Ta, about 6.0-7.0 Cr, about 6.25-7.0 W, about 1.5-2.5 Mo, about 0.15-0.60 Hf, 0.0-1.0 Re, 6.5-9.0 Co, optionally, 0.03-0.06 C, optionally, up to about 0.004 B, optionally up to about 0.03 total of one or more rare earth elements selected from yttrium (Y), lanthanum (La), or cerium (Ce), balance nickel, such that the superalloy composition exhibits a stress rupture capability improvement of at least 15% over a base stress rupture capability of a base composition nominally comprising, in weight percent: 6.5 Al, 6.6 Ta, 6.0 Cr, 6.25 W, 1.5 Mo, 0.15 Hf, 0.0 Re, 7.5 Co. Articles incorporating the superalloy composition include a gas turbine engine component such as a high pressure turbine nozzle or nozzle segment.

Abstract: A ductile corrosion and oxidation resistant coating, being predominately of gamma-prime nickel aluminide intermetallic includes 15-30 atomic % aluminum, up to atomic % chromium, optionally, up to 30 atomic % of a platinum group metal, optionally, up to 4 atomic % of a reactive element, and optionally, up to 15 atomic % of at least one strengthening element, and a balance being essentially nickel or nickel and at least one of cobalt, iron, or cobalt and iron. A coated article includes the ductile corrosion and oxidation resistant coating on a superalloy substrate such as a turbine disk, turbine seal, a turbine blade, a turbine nozzle, a turbine shroud, or a turbine frame or case having an under platform or non-gas path region.

Abstract: Method includes providing a superalloy substrate such as a turbine disk, a turbine seal, a turbine blade, a turbine nozzle, a turbine shroud, or a turbine frame or case having an under platform or non-gas path region; and providing a predominantly gamma-prime nickel aluminide intermetallic ductile corrosion and oxidation resistant coating disposed on at least a portion of the substrate. The coating comprises from about 15 to about 30 atomic % aluminum, up to about 20 atomic % chromium, optionally, up to about 30 atomic % of at least one platinum group metal, optionally, up to about 4 atomic % of at least one reactive element, and optionally, up to about 15 atomic % of at least one strengthening element, and a balance being essentially nickel or nickel and at least one of cobalt, iron, or cobalt and iron. A coating precursor composition may be applied to the substrate before or after optional plating with one or more platinum group metals.

Abstract: A coating system and a method for forming the coating system, the method including coating a surface of a gas turbine engine turbine component having a metallic surface that is outside the combustion gas stream and exposed to cooling air during operation of the engine. A gel-forming solution including a ceramic metal oxide precursor is provided. The gel-forming solution is heated to a first preselected temperature for a first preselected time to form a gel. The gel is then deposited on the metallic surface. Thereafter the gel is fired at a second preselected temperature above the first preselected temperature to form a ceramic corrosion resistant coating comprising a ceramic metal oxide is selected from the group consisting of zirconia, hafnia and combinations thereof. The ceramic corrosion resistant coating having a thickness of up to about 127 microns and remaining adherent at temperatures greater than about 1000° F.

Abstract: A process by which a nickel-based superalloy substrate prone to deleterious reactions with an aluminum-rich coating can be stabilized by carburization. The process generally entails processing the surface of the substrate to be substantially free of oxides, heating the substrate in a non-oxidizing atmosphere to a carburization temperature, and then contacting the surface of the substrate with a carburization gas mixture comprising a diluted low activity hydrocarbon gas while maintaining the substrate at the carburization temperature. While at the carburization temperature and contacted by the carburization gas, carbon atoms in the carburization gas dissociate therefrom, transfer onto the surface of the substrate, diffuse into the substrate, and react with refractory metals within the substrate to form refractory metal carbides within a carburized region beneath the surface of the substrate. The substrate is then cooled in a non-oxidizing atmosphere to terminate carbide formation.

Abstract: A nickel-base superalloy composition including (measured in % by weight) from about 6.5 to about 7.5% aluminum, from about 4 to about 8% tantalum, from about 3 to about 10% chromium, from about 2 to about 7% tungsten, from 0 to about 4% molybdenum, from 0 to about 6% rhenium, from 0 to less than about 0.001% niobium, from 0 to about 5% cobalt, from 0 to about 0.2% silicon, from 0 to about 0.06% carbon, optionally, from 0 to about 0.5% titanium, from 0 to about 0.005% boron, from about 0.15 to about 0.7% hafnium, from 0 to about 0.03% of a rare earth addition selected from the group consisting of yttrium, lanthanum, cesium, and combinations thereof, balance nickel and incidental impurities. The nickel-base superalloy composition may be used in single-crystal or directionally solidified superalloy articles such as high pressure turbine blades for a gas turbine engine.

Abstract: A composition comprising a glass-forming binder component and a particulate corrosion resistant component. The particulate corrosion resistant component comprises corrosion resistant particulates having: a CTEp of at least about 4 and being solid at a temperature of about 1300° F. (704° C.) or greater; and a maximum median particle size defined by one of the following formulas: (a) for a CTEp of 8 or less, an MP equal to or less than (4.375×CTEp)?10; and (b) for a CTEp of greater than 8, an Mp equal to or less than (?4.375×CTEp)+60, wherein CTEp is the average CTE of the corrosion resistant particulates and wherein Mp is the median equivalent spherical diameter (ESD), in microns, of the corrosion resistant particulates. Also disclosed is an article comprising a turbine component comprising a metal substrate and a corrosion resistant coating overlaying the metal substrate, as well as a method for forming at least one layer of the corrosion resistant coating adjacent to the metal substrate.

Abstract: Methods of making components having calcium magnesium aluminosilicate (CMAS) mitigation capability involving providing a component; applying an environmental barrier coating to the component, the environmental barrier coating having a separate CMAS mitigation layer including a CMAS mitigation composition selected from rare earth elements, rare earth oxides, zirconia, hafnia partially or fully stabilized with alkaline earth or rare earth elements, zirconia partially or fully stabilized with alkaline earth or rare earth elements, magnesium oxide, cordierite, aluminum phosphate, magnesium silicate, and combinations thereof.

Abstract: Calcium magnesium aluminosilicate (CMAS) mitigation compositions selected from rare earth elements, rare earth oxides, zirconia, hafnia partially or fully stabilized with alkaline earth or rare earth elements, zirconia partially or fully stabilized with alkaline earth or rare earth elements, magnesium oxide, cordierite, aluminum phosphate, magnesium silicate, and combinations thereof when the CMAS mitigation composition is included as a separate CMAS mitigation layer in an environmental barrier coating for a high temperature substrate component.

Abstract: A composition useful as a thermal barrier coating on a superalloy substrate intended for use in hostile thermal environments. The coating comprises zirconia stabilized in a predominately tetragonal phase. The composition includes a ceramic component consisting essentially of zirconia (ZrO2) or a combination of zirconia and hafnia (HfO2) and a stabilizer component comprising, in combination, a first co-stabilizer selected from YbO1.5, HoO1.5, ErO1.5, TmO1.5, LuO1.5, and combinations thereof, and a second co-stabilizer selected from TiO2, PdO2, VO2, GeO2, and combinations thereof. Optionally, the stabilizer component includes Y2O3. The stabilizer component is present in an amount effective to achieve the predominantly tetragonal phase in the coating.

Abstract: A composition useful as a thermal barrier coating on a superalloy substrate intended for use in hostile thermal environments. The coating comprises zirconia stabilized in a predominately tetragonal phase. The composition includes a ceramic component consisting essentially of zirconia (ZrO2) or a combination of zirconia and hafnia (HfO2) and a stabilizer component comprising, in combination, a first co-stabilizer selected from YbO1.5, HoO1.5, ErO1.5, TmO1.5, LuO1.5, and combinations thereof, and optionally YO1.5, a second co-stabilizer selected from TiO2, PdO2, VO2, GeO2, and combinations thereof, and a third co-stabilizer comprising TaO2.5. The stabilizer component is present in an amount effective to achieve the predominantly tetragonal phase in the coating.

Abstract: Slurry coating process for selectively enriching surface regions of a metal-based substrate, for example, the under-platform regions of a turbine blade, with chromium. The process employs a slurry coating composition containing metallic chromium, optionally metallic aluminum in a lesser amount by weight than chromium, and optionally other constituents. The composition further includes colloidal silica, and may also include one or more additional constituents, though in any event the composition is substantially free of hexavalent chromium and sources thereof. The coating composition is applied to a surface region to form a slurry coating, which is then heated to remove any volatile components of the coating composition and thereafter cause diffusion of chromium from the coating into the surface region to form a chromium-rich diffusion coating.

Abstract: A protective coating for use on a silicon-containing substrate, and deposition methods therefor. The coating has a barium-strontium-aluminosilicate (BSAS) composition that is less susceptible to degradation by volatilization and in corrosive environments as a result of having at least an outer surface region that consists essentially of one or more stoichiometric crystalline phases of BSAS and is substantially free of a nonstoichiometric second crystalline phase of BSAS that contains a substoichiometric amount of silica. The coating can be produced by carrying out deposition and heat treatment steps that result in the entire coating or just the outer surface region of the coating consisting essentially of the stoichiometric celsian phase.

Abstract: According to an embodiment of the invention, an article of manufacture for use in a gas turbine engine is disclosed. The article comprises a part having a surface covered with a ceramic thermal barrier coating. The thermal barrier coating has an outer surface covered with a sacrificial phosphate coating, wherein the sacrificial phosphate coating reacts with contaminant compositions to prevent contaminant infiltration into the thermal barrier coating.

Abstract: An article comprising a turbine component other than an airfoil having a metal substrate and a ceramic corrosion resistant coating overlaying the metal substrate. This coating has a thickness up to about one micrometer and consists of a ceramic composition that comprises a ceramic metal oxide selected from the group consisting of zirconia, hafnia and mixtures thereof. This coating can be formed by alternative methods to have different microstructures, including a dense matrix or a strain-tolerant columnar grain structure.