Abstract: Thermal barrier coating systems for use with hot section components of a gas turbine engine include an inner layer overlying a bond coated substrate and a top layer overlying at least a portion of the inner layer. The inner layer includes a thermal barrier material such as yttria-stabilized zirconia. The top layer includes a rare earth aluminate. The thicknesses and microstructures of the layers may be varied depending on the type of component to be coated.

Abstract: Methods for coating a substrate includes depositing on the substrate, a inner bond coat layer of a bond coat composition comprising, in weight percent, 14-20% Cr, 5-8% Al, 8-12% Co, 3-7% Ta, 0.1-0.6% Hf, 0.1-0.5% Y, up to about 1% Si, 0.005-0.020% Zr, 0.04-0.08% C, 0.01-0.02% B, with a remainder including nickel (Ni) and incidental impurities, wherein the bond coat composition is substantially free of rhenium; forming an aluminum-containing layer overlying the inner bond coat layer; and, optionally, depositing a thermal barrier coating composition overlying the aluminum-containing layer.

Abstract: Coating system for a metallic substrate includes a strengthened bond coat including a bond coat inner layer and an aluminum-containing layer overlying the bond coat inner layer. The bond coat inner layer is formed by deposition of a bond coat composition including, in weight percent, 14-20% Cr, 5-8% Al, 8-12% Co, 3-7% Ta, 0.1-0.6% Hf, 0.1-0.5% Y, up to about 1% Si, 0.005-0.020% Zr, 0.04-0.08% C, 0.01-0.02% B, with a remainder including Ni and incidental impurities, wherein the bond coat composition is substantially free of rhenium. The coating system includes an optional thermal barrier coating which may be a yttria-stabilized zirconia.

Abstract: Coated superalloy article includes a bond coat comprising an inner bond coat layer disposed on the first surface being formed by deposition of a bond coat composition comprising, in weight percent, 14-20% Cr, 5-8% Al, 8-12% Co, 3-7% Ta, 0.1-0.6% Hf, 0.1-0.5% Y, up to about 1% Si, 0.005-0.020% Zr, 0.04-0.08% C, 0.01-0.02% B, with a remainder including nickel (Ni) and incidental impurities, wherein the bond coating composition is substantially free of rhenium. An aluminum-containing layer overlies the inner bond coat layer. Optionally, a thermal barrier coating overlies the aluminum-containing layer, wherein the thermal barrier coating, if present, is formed by deposition of a thermal barrier coating composition.

Abstract: The present invention is a gas turbine engine turbine blade comprising an airfoil section having at least an exterior surface, a platform section having an exterior surface, an under platform section having an exterior surface, and a dovetail section having an exterior surface. The blade further comprises a corrosion resistant coating on a surface of a turbine blade section selected from the group consisting of the exterior surface of the under platform section, the exterior surface of the dovetail section, and combinations thereof, the corrosion resistant coating comprising a particulate corrosion resistant component comprising from about 5 weight percent to about 100 weight percent corrosion resistant non-alumina particulates having a CTE greater than that of alumina particulates and balance alumina particulates, and a binder component. The present invention also includes methods for making such a gas turbine engine blade.

Abstract: A thermal barrier coating and deposition process for a component intended for use in a hostile thermal environment, such as the turbine, combustor and augmentor components of a gas turbine engine. The TBC has a first coating portion on at least a first surface portion of the component. The first coating portion is formed of a ceramic material to have at least an inner region, at least an outer region overlying the inner region, and a columnar microstructure whereby the inner and outer regions comprise columns of the ceramic material. The columns of the inner region are more closely spaced than the columns of the outer region so that the inner region of the first coating portion is denser than the outer region of the first coating portion, wherein the higher density of the inner region promotes the impact resistance of the first coating portion.

Abstract: An article comprising a substrate formed of a silicon-comprising material, such as an article exposed to the hostile thermal environment of a gas turbine engine. The article further comprises an environmental barrier layer, e.g., an alkaline earth metal aluminosilicate, and a physical barrier layer overlying the environmental barrier layer. The physical barrier layer comprises zirconia or hafnia stabilized with an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals; and a low CTE oxide selected from the group consisting of niobia and tantala; and mixtures thereof. A method for preparing an environmental barrier coating system on a substrate formed of a silicon-comprising material is also disclosed.

Abstract: A coating system for Si-containing materials, particularly Si-based composites used to produce articles exposed to high temperatures. The coating system is a compositionally-graded thermal/environmental barrier coating (T/EBC) system that includes an intermediate layer containing yttria-stabilized hafnia (YSHf) and mullite, alumina and/or an aluminosilicate, which is used in combination with an inner layer between a Si-containing substrate and the intermediate layer and a thermal-insulating top coat overlying the intermediate layer. The intermediate layer provides environmental protection to the silicon-containing substrate, and has a coefficient of thermal expansion between that of the top coat and that of the inner layer so as to serve as a transition layer therebetween. The intermediate layer is particular well suited for use in combination with an inner layer of an alkaline earth metal aluminosilicate (such as BSAS) and a top coat formed of YSZ or YSHf.

Abstract: A process for protecting a thermal barrier coating (TBC) on a component used in a high-temperature environment, such as the hot section of a gas turbine engine. The process applies a protective film on the surface of the TBC to resist infiltration of contaminants such as CMAS that can melt and infiltrate the TBC to cause spallation. The process generally entails applying to the TBC surface a metal composition containing at least one metal whose oxide resists infiltration of CMAS into the TBC. The metal composition is applied so as to form a metal film on the TBC surface and optionally to infiltrate porosity within the TBC beneath its surface. The metal composition is then converted to form an oxide film, with at least a portion of the oxide film forming a surface deposit on the TBC surface.

Abstract: Methods for coating a turbine engine rotor component involving depositing at least one platinum group metal selected from platinum, palladium, rhodium, ruthenium, iridium and osmium on the rotor component, and heating the rotor component to a temperature of from about 500° C. to about 800° C.

Abstract: A gas turbine engine nozzle segment and process for producing such a nozzle segment to exhibit improved durability and aerodynamic performance. The process produces a nozzle segment having at least one vane between and interconnecting a pair of platforms. The nozzle segment is cast from a gamma prime-strengthened nickel-base superalloy, on whose surface is thermal sprayed an environmental coating formed of a MCrAlX-type coating material. The surface of the environmental coating is then worked to cause the coating to have a surface finish of less than 2.0 micrometers Ra. Cooling holes are then drilled in the nozzle segment, after which an oxidation-resistant coating is applied on the smoothed surface of the nozzle segment so as to maintain an outermost surface on the nozzle segment having surface finish of less than 2.0 micrometers Ra.

Abstract: An article comprising a substrate formed of a silicon-comprising material, such as an article exposed to the hostile thermal environment of a gas turbine engine. The article further comprises an environmental barrier layer, e.g., an alkaline earth metal aluminosilicate, and a top coat comprising hafnia stabilized with from about 0.5 mole % to about 10 mole % of an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals, and mixtures thereof. The article optionally comprises a transition layer between the environmental barrier layer and the top coat. A method for preparing a thermal/environmental barrier coating on a substrate formed of a silicon-comprising material is also disclosed.

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: The present invention is a gas turbine engine turbine blade comprising an airfoil section having at least an exterior surface, a platform section having an exterior surface, an under platform section having an exterior surface, and a dovetail section having an exterior surface. The blade further comprises a corrosion resistant coating on a surface of a turbine blade section selected from the group consisting of the exterior surface of the under platform section, the exterior surface of the dovetail section, and combinations thereof, the corrosion resistant coating comprising a particulate corrosion resistant component comprising from about 5 weight percent to about 100 weight percent corrosion resistant non-alumina particulates having a CTE greater than that of alumina particulates and balance alumina particulates, and a binder component. The present invention also includes methods for making such a gas turbine engine blade.

Abstract: A protected article includes a substrate having a surface, and a protective system overlying and contacting a first portion of the surface of the substrate. The protective system has a nickel-base superalloy bond coat, an aluminide layer overlying and contacting the bond coat, and a dense vertically microcracked ceramic thermal barrier coating overlying and contacting the aluminide layer.

Abstract: A thermal barrier coating for an underlying metal substrate of articles that operate at, or are exposed to, high temperatures, as well as being exposed to environmental contaminant compositions. This coating comprises an inner layer nearest to the underlying metal substrate comprising a ceramic thermal barrier coating material, as well as an outer layer having an exposed surface and comprising a CMAS-reactive material in an amount up to 100% and sufficient to protect the thermal barrier coating at least partially against CMAS that becomes deposited on the exposed surface, the CMAS-reactive material comprising an alkaline earth aluminate or alkaline earth aluminosilicate where the alkaline earth is selected from barium, strontium and mixtures thereof, and optionally a ceramic thermal barrier coating material. This coating can be used to provide a thermally protected article having a metal substrate and optionally a bond coat layer adjacent to and overlaying the metal substrate.

Abstract: A high temperature gas turbine component for use in the gas flow path that comprises a specular optical reflector coating system. A thin specular optical reflector coating system is applied to the gas flow path of the component, that is, the surface of the component that forms a boundary for hot combustion gases. The component typically includes a thermal barrier coating overlying the high temperature metallic component that permits the component to operate at elevated temperatures. The thermal barrier coating must be polished in order to provide a surface that can suitably reflect the radiation into the gas flow path. The thin reflector coating system comprises a thin high temperature and corrosion resistant refractory stabilizing layer, which is applied over a thin reflective metal layer, which is applied over a thin high temperature and corrosion resistant refractory sealing layer.

Abstract: An article comprising a substrate formed of a silicon-comprising material, such as an article exposed to the hostile thermal environment of a gas turbine engine. The article further comprises an environmental barrier layer, e.g., an alkaline earth metal aluminosilicate, and a top coat comprising zirconia or hafnia stabilized with up to about 10 mole % of an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals, and mixtures thereof. The article further comprises a transition layer between the environmental barrier layer and the top coat, the transition layer comprising zirconia or hafnia stabilized with up to about 10 mole % of an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals; and a low CTE oxide selected from the group consisting of niobia and tantala; and mixtures thereof.

Abstract: An article comprising a substrate formed of a silicon-comprising material, such as an article exposed to the hostile thermal environment of a gas turbine engine. The article further comprises an environmental barrier layer, e.g., an alkaline earth metal aluminosilicate, and a top coat comprising zirconia or hafnia stabilized with an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals, and mixtures thereof. The article further comprises a transition layer between the environmental barrier layer and the top coat, the transition layer comprising zirconia or hafnia stabilized with an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals; and a low CTE oxide selected from the group consisting of niobia and tantala; and mixtures thereof. A method for preparing a thermal/environmental barrier coating system on a substrate formed of a silicon-comprising material is also disclosed.

Abstract: A method applying a thermal barrier coating to a metal substrate, or for repairing a thermal barrier coating previously applied by physical vapor deposition to an underlying aluminide diffusion coating that overlays the metal substrate. The aluminide diffusion coating is treated to make it more receptive to adherence of a plasma spray-applied overlay alloy bond coat layer. An overlay alloy bond coat material is then plasma sprayed on the treated aluminide diffusion coating to form an overlay alloy bond coat layer. A ceramic thermal barrier coating material is plasma sprayed on the overlay alloy bond coat layer to form the thermal barrier coating. In the repair embodiment of this method, the physical vapor deposition-applied thermal barrier coating is initially removed from the underlying aluminide diffusion coating.