Abstract: A method of forming a metal coating on surfaces of internal passages of a turbine blade includes, in an exemplary embodiment, the steps of positioning the turbine blade in a CVD chamber, coupling a reagent gas manifold to at least one internal passage inlet, and coating the surfaces of the at least one internal passage by a CVD process using metal coating reagent gases to form a metal coating on the surfaces of the at least one internal passage.

Abstract: A method for applying a thermal barrier coating to an article having cooling holes and concurrently cleaning obstructions, such as TBC overspray or other debris, from those holes is disclosed. A thermal barrier coating is applied to a first surface of an article having cooling holes. Concurrently therewith, a plurality of particles are projected against a second surface of the article, such that at least some of the particles pass through the cooling holes, strike the overspray constituents prior to cooling, knocking at least some of the obstructions out of the cooling hole.

Abstract: A method for applying a thermal barrier coating to an article having cooling holes and concurrently cleaning obstructions, such as TBC overspray or other debris, from those holes is disclosed. A thermal barrier coating is applied to a first surface of an article having cooling holes. Concurrently therewith, a plurality of particles are projected against a second surface of the article, such that at least some of the particles pass through the cooling holes, strike the overspray constituents prior to cooling, knocking at least some of the obstructions out of the cooling hole.

Abstract: A method is provided for electroplating a high temperature coating onto an airfoil. The method includes providing a shield having a recess defining one or more walls conforming to the shape of at least a portion of a pressure side and a suction side of the airfoil to be electroplated, introducing the portions of the pressure side and the suction side of the airfoil to be electroplated into the recess of the shield, attaching an anode and cathode to the airfoil, submerging at least the shield and the portions of the pressure side and the suction side of the airfoil to be electroplated into an electroplating tank containing an electrolyte, and electroplating a coating of a high temperature resistant metal onto the portions of the pressure side and the suction side of the airfoil to be electroplated to a predetermined minimum thickness.

Abstract: A chemically-nonreactive, electrically-nonconductive shield having a recess generally corresponding to the shape of an airfoil portion to be positioned therein. The shield is submerged in an electroplating solution in a plating tank. The recess in the shield is sized to provide a predetermined, closely-spaced apart clearance gap between walls of the recess and the adjacent airfoil portion sufficient to reduce the flow rate of an electrolyte present in the electroplating solution between walls of the recess and the adjacent airfoil portion. The clearance gap permits control of the amount of electroplating that is deposited on the airfoil portion that is positioned within the recess in relation to portions of the airfoil not positioned within the recess.

Abstract: A method of forming a metal coating on surfaces of internal passages of a turbine blade includes, in an exemplary embodiment, the steps of positioning the turbine blade in a CVD chamber, coupling a reagent gas manifold to at least one internal passage inlet, and coating the surfaces of the at least one internal passage by a CVD process using metal coating reagent gases to form a metal coating on the surfaces of the at least one internal passage.

Abstract: A method facilitates replacing a portion of a gas turbine engine turbine support. The turbine support includes a body including a forward leg, an aft leg, and a mounting flange that each extend radially outwardly from the body. The forward leg is axially upstream from the aft leg and the mounting flange. The mounting flange is substantially axially aligned with respect to the aft leg. The method comprises cutting through at least one of the body, the aft leg, and the mounting flange, removing the forward leg and at least a portion of the body that is upstream from the cut from the engine, and coupling a replacement spad to the portion of the turbine support that is downstream from the cut.

Abstract: A method facilitates replacing a portion of a gas turbine engine turbine support. The turbine support includes a body including a forward leg, an aft leg, and a mounting flange that each extend radially outwardly from the body. The forward leg is axially upstream from the aft leg and the mounting flange. The mounting flange is substantially axially aligned with respect to the aft leg. The method comprises cutting through at least one of the body, the aft leg, and the mounting flange, removing the forward leg and at least a portion of the body that is upstream from the cut from the engine, and coupling a replacement spad to the portion of the turbine support that is downstream from the cut.

Abstract: A thermal barrier coating system and a method for forming the coating system on an article designed for use in a hostile thermal environment. The method is particularly directed to a coating system that includes a plasma-sprayed MCrAlY bond coat on which a thermal-insulating APS ceramic layer is deposited, in which the oxidation resistance of the bond coat and the spallation resistance of the ceramic layer are substantially increased by vapor phase aluminizing the bond coat. The bond coat is deposited to have a surface area ratio of at least 1.4 and a surface roughness of at least 300 &mgr;inch Ra in order to promote the adhesion of the ceramic layer. The bond coat is then overcoat aluminized using a vapor phase process that does not alter the surface area ratio of the bond coat. This process is carried out at relatively low temperatures that promote inward diffusion of aluminum relative to outward diffusion of the bond coat constituents, particularly nickel and other refractory elements.

Abstract: A thermal barrier coating system and a method for forming the coating system on a component designed for use in a hostile thermal environment, such as superalloy turbine, combustor and augmentor components of a gas turbine engine. The coating system includes a diffusion aluminide bond coat whose oxide growth rate is significantly reduced to improve the spallation resistance of a thermal barrier layer by forming the bond coat to include a dispersion of aluminum, chromium, nickel, cobalt and/or platinum group metal oxides. The oxides preferably constitute about 5 to about 20 volume percent of the bond coat. A preferred method of forming the bond coat is to initiate a diffusion aluminizing process in the absence of oxygen to deposit a base layer of diffusion aluminide, and then intermittently introduce an oxygen-containing gas into the diffusion aluminizing process to form within the bond coat the desired dispersion of oxides.

Abstract: An article comprising a substrate and an outer metallic layer, such as a coating, is provided with augmented heat transfer from the substrate through the combination of a layer thickness of about 0.003″ to about 0.017″, a layer surface roughness of at least about 500 micro inches Ra, a layer tensile bond strength of at least about 5 ksi, and a heat transfer augmentation of at least about 1.1. A method of making the article uses an electric arc wire thermal spray process in which the atomizing gas pressure is maintained within the range of about 20-80 psi.

Abstract: An article comprising a substrate and an outer metallic layer, such as a coating, is provided with augmented heat transfer from the substrate through the combination of a layer thickness of about 0.003″ to about 0.017″, a layer surface roughness of at least about 500 micro inches Ra, a layer tensile bond strength of at least about 5 ksi, and a heat transfer augmentation of at least about 1.1. A method of making the article uses an electric arc wire thermal spray process in which the atomizing gas pressure is maintained within the range of about 20-80 psi.

Abstract: A thermal barrier coating system and a method for forming the coating system on a component designed for use in a hostile thermal environment, such as superalloy turbine, combustor and augmentor components of a gas turbine engine. The coating system includes a diffusion aluminide bond coat whose oxide growth rate is significantly reduced to improve the spallation resistance of a thermal barrier layer by forming the bond coat to include a dispersion of aluminum, chromium, nickel, cobalt and/or platinum group metal oxides. The oxides preferably constitute about 5 to about 20 volume percent of the bond coat. A preferred method of forming the bond coat is to initiate a diffusion aluminizing process in the absence of oxygen to deposit a base layer of diffusion aluminide, and then intermittently introduce an oxygen-containing gas into the diffusion aluminizing process to form within the bond coat the desired dispersion of oxides.

Abstract: A thermal barrier coating system and a method for forming the coating system on an article designed for use in a hostile thermal environment, such as superalloy turbine, combustor and augmentor components of a gas turbine engine. The method is particularly directed to a coating system comprising an APS bond coat on which a thermal-insulating APS ceramic layer is deposited, wherein the oxidation resistance of the bond coat and the spallation resistance of the ceramic layer are increased by diffusing platinum, palladium, hafnium, rhenium and/or rhodium into the bond coat. The diffusion process is performed so as not to alter the surface roughness of the bond coat, which is maintained in a range of about 200 to about 500.mu. inch Ra.

Abstract: A fluid cooled article having a protective coating on a surface, for example an air cooled gas turbine engine article having a Thermal Barrier Coating, includes through an article wall a fluid cooling passage, and typically a plurality of passages, having openings sized to maintain desired fluid flow, unobstructed by coating within the passage at an exit opening. The passage has a first or inlet opening, which establishes the amount of fluid flow through the passage, and a second opening through which the flow exits the passage through a wall surface on which the coating is deposited.

Abstract: A thermal barrier coating system and a method for forming the coating system on an article designed for use in a hostile thermal environment, such as superalloy turbine, combustor and augmentor components of a gas turbine engine. The method is particularly directed to a coating system comprising an APS bond coat on which a thermal-insulating APS ceramic layer is deposited, wherein the oxidation resistance of the bond coat and the spallation resistance of the ceramic layer are increased by diffusing platinum, palladium, hafnium, rhenium and/or rhodium into the bond coat. The diffusion process is performed so as not to alter the surface roughness of the bond coat, which is maintained in a range of about 200 to about 500 .mu.inch Ra.

Abstract: A fluid cooled article having a protective coating on a surface, for example an air cooled gas turbine engine article having a Thermal Barrier Coating, includes through an article wall a fluid cooling passage, and typically a plurality of passages, having openings sized to maintain desired fluid flow, unobstructed by coating within the passage at an exit opening. The passage has a first or inlet opening, which establishes the amount of fluid flow through the passage, and a second opening through which the flow exits the passage through a wall surface on which the coating is deposited.

Abstract: A method of repairing a thermal barrier coating on an article designed for use in a hostile thermal environment, such as turbine, combustor and augmentor components of a gas turbine engine. The method is particularly suited for the repair of thermal barrier coatings composed of a metallic bond layer formed on the surface of the article, and a columnar ceramic layer overlaying the bond layer. The method entails the steps of cleaning the bond layer exposed by localized spallation, treating the bond layer so as to texture its exposed surface, and then depositing a ceramic material on the surface of the bond layer so as to form a ceramic repair layer that completely covers the bond layer. Deposition of the repair layer can be carried out such that its upper surface projects above the adjacent ceramic layer, followed by abrading the repair layer to a height substantially level with the ceramic layer.

Abstract: A thermal barrier coating is provided which is adapted to be formed on an article subjected to a hostile thermal environment while subjected to thermally, mechanically and/or dynamically-induced stresses, such as a component of a gas turbine engine. The thermal barrier coating is composed of a bond layer that tenaciously adheres an insulative ceramic layer to the article. The bond layer is formed of a metallic oxidation-resistant material, and has an average surface roughness R.sub.a of at least about 7.5 micrometers, while the ceramic layer is characterized by being segmented by at least two sets of grooves. The grooves have substantially uniform widths of about 100 to about 500 micrometers, with adjacent grooves of each set being spaced about 10 to about 250 millimeters apart.

Abstract: A thermal barrier coating is provided which is adapted to be formed on an article subjected to a hostile thermal environment while subjected to thermally, mechanically and/or dynamically-induced stresses, such as a component of a gas turbine engine. The thermal barrier coating is composed of a bond layer that tenaciously adheres an insulative ceramic layer to the article. The bond layer is formed of a metallic oxidation-resistant material, and has an average surface roughness R.sub.a of at least about 7.5 micrometers, while the ceramic layer is characterized by being segmented by at least two sets of grooves. The grooves have substantially uniform widths of about 100 to about 500 micrometers, with adjacent grooves of each set being spaced about 10 to about 250 millimeters apart.