Abstract: Exemplary embodiments of the invention provide barrier coated substrates and methods of coating a substrate with a barrier coating derived from sol gels. An example includes a barrier coated aerospace component that is subject to hot salt corrosion during use. The barrier coating is derived from oxidation of a coating composition that includes at least one sol gel. The barrier coating resists hot salt corrosion for an incubation period of such duration that an uncoated superalloy substrate under the same conditions would suffer corrosion to a depth of about 2.0 mils. Methods of applying the barrier coating include the steps of selecting a first liquid sol gel and wetting surfaces of the superalloy substrate with the selected first liquid sol gel. The wetted surfaces of the superalloy substrate are subjected to heat treatment. The heat treatment includes sintering of sol gel to oxide to produce a barrier coating.

Abstract: A turbine blade tip and shroud clearance control coating system comprising an abrasive blade tip coating and an abradable shroud coating are provided. The abrasive layer may comprise abrasive particles of cubic zirconia, cubic hafnia or mixtures thereof, and the abradable layer may be a nanolaminate thermal barrier coating that is softer than the abrasive layer. The invention further provides an alternate coating system comprising an abradable blade tip coating and an abrasive shroud coating.

Abstract: A protective barrier coating system including a diffusion barrier coating and an oxidation barrier coating and method for use in protecting silicon-based ceramic turbine engine components. A complete barrier coating system includes a thermal barrier coating of stabilized zirconia and an environmental barrier coating of an alloyed tantalum oxide. The oxidation barrier coating includes a layer of metallic silicates formed on a substrate of silicon nitride or silicon carbide to be protected. The oxidation barrier coating can include silicates of scandium, ytterbia or yttrium. The oxidation barrier coating may also include an inner layer of Si2ON2 between the diffusion barrier and the metallic silicate layer. The oxidation barrier coating can be applied to the substrate by spraying, slurry dipping and sintering, by a sol-gel process followed by sintering, by plasma spray, or by electron beam-physical vapor deposition.

Abstract: A layered structure includes a substrate comprising a layer of an oxide/oxide ceramic based composite material, a first oxide layer disposed directly on the substrate and formed from a material that has no greater than about 10% porosity and is substantially impermeable by water vapor, and a second oxide layer disposed directly on the first oxide layer and having a greater porosity than the first oxide layer. Either or both the first and second oxide layers of the coating system may be deposited using a plasma spraying process, a slurry deposition process which is followed by a sintering step, or an EB-PVD process.

Abstract: A component comprising a silicon-based substrate and a diffusion barrier coating disposed on the silicon-based substrate. The diffusion barrier coating comprises an isolation layer disposed directly on the silicon-based substrate and at least one oxygen barrier layer disposed on the isolation layer. The oxygen barrier layer prevents the diffusion of oxygen therethrough, and prevents excessive oxidation of the silicon-based substrate. The isolation layer(s) prevent contaminants and impurities from reacting with the oxygen barrier layer. An environmental barrier coating may be disposed on the diffusion barrier coating, and a thermal barrier coating may be disposed on the environmental barrier coating. Methods for making a component having a diffusion barrier coating are also disclosed.

Abstract: A durable protective coating may be formed by applying a thin layer of metastable alumina to a bond coating on a substrate. A thermal barrier coating may then be applied to the metastable alumina and the resulting part may be heat treated to transform the metastable alumina to a mixed alpha alumina having particles of the thermal barrier coating, such as zirconia in the case of an yttria stabilized zirconia thermal barrier coating, dispersed therein. The resulting thermal barrier coating may inhibit microbuckling of the thermally grown oxide scale that grows over time at the thermal barrier coating-bond coating interface.

Abstract: The invention provides hard, ductile coatings comprising a ductile bonding layer of zirconium or titanium alloyed with a precious metal and a hard, surface layer comprising at least one compound selected from the group consisting of zirconium nitride, titanium nitride, zirconium carbide and titanium carbide and a precious metal segregated into the grain boundaries. The present invention also provides hard ductile multilayer coatings comprised of alternating ductile metal and hard nitride or carbide layers. The invention also includes methods to manufacture nitride or carbide coatings with ductile precious metal grain boundaries. The coatings provide an erosion resistant coating to surfaces to which they are applied.

Abstract: A method of modifying a turbine nozzle area comprises depositing a thermal barrier coating (TBC) on the nozzle endwalls to provide a minimum nozzle area, evaluating an airflow through the nozzle, and machining the TBC to increase the nozzle area. Adjacent segment area variation may be minimized, improving engine reliability by reducing the aerodynamic excitation to the down stream blade.

Abstract: A thermal barrier coating for a gas turbine component includes a bond coating layer, at least a first segmented columnar ceramic layer on the bond coating layer, and a particulate structure-stabilizing material disposed within a plurality of segmentation gaps within the columnar ceramic layer(s). The thermal barrier coating may further comprise, a second segmented columnar ceramic layer of yttria stabilized hafnia on the first segmented columnar ceramic layer, and an outer, continuous, non-segmented sealant layer covering the yttria stabilized hafnia layer to prevent ingress of extraneous materials into the segmentation gaps. Methods for depositing a thermal barrier coating on a substrate are also disclosed.

Abstract: A component comprising a silicon-based substrate and a braze-based protective coating disposed on the silicon-based substrate. The braze-based coating comprises a brazed layer, wherein the brazed layer comprises at least one intermetallic compound. A scale layer may be formed on the brazed layer. An environmental barrier coating may be disposed directly on the brazed layer or directly on the scale layer. A thermal barrier coating may be disposed on the environmental barrier coating. Methods for making a Si-based component having a braze-based protective coating are also disclosed.

Abstract: The present application relates to a method of producing a metal article having an internal passage coated with a ceramic coating. The method comprises: preparing a core for defining the internal passage; applying the ceramic coating on the core; assembling the core with the ceramic coating applied thereon into a mold; casting metal into the mold at a pour temperature lower than the melting temperature of the ceramic coating; and removing the core. The ceramic coating may be applied by plasma spraying or slurry deposition.

Abstract: A lightweight high temperature bladed turbine disk intended for use in gas turbine engines. The bladed disk comprises a cast integral ring of single crystal airfoils with the primary and secondary crystallographic orientation being the same for each airfoil. Low-angle mismatch boundaries are present in the endwalls that couple adjacent airfoils. The cast ring of single crystal turbine blades is diffusion bonded to a high strength equiaxed disk. The resulting single crystal bladed disk is endowed superior performance, temperature capability, and lower weight and cost, relative to conventional turbines composed of individually cast single crystal blades, which are mechanically inserted into machined slots in the disk, or lower strength cast equiaxed blade rings that are diffusion bonded to a high strength turbine disk.

Abstract: A method for forming a carbon deposit inhibiting thermal barrier coating for an internal element or component of a gas turbine engine. Such coating includes a layer of thermal barrier material coated onto the surface of an engine component that will be exposed to the flow of burning engine gases. Such coating further includes a layer of carbon deposit inhibiting material coated on top of the layer of thermal barrier material.

Abstract: A carbon deposit inhibiting thermal barrier coating for an internal element or component in a gas turbine engine. Such coating includes a layer of thermal barrier material coated onto the surface of an engine component that will be exposed to the flow of burning engine gases. Such coating further includes a layer of carbon deposit inhibiting material coated on top of the layer of thermal barrier material.

Abstract: A carbon deposit inhibiting thermal barrier coating for an internal element or component in a gas turbine engine. Such coating includes a layer of thermal barrier material coated onto the surface of an engine component that will be exposed to the flow of burning engine gases. Such coating further includes a layer of carbon deposit inhibiting material coated on top of the layer of thermal barrier material.

Abstract: Methods and apparatus to make multilayer thermal barrier coatings for superalloy substrates such as turbine blades or vanes are disclosed. The methods produce non-homogeneous, nanometer-size, successive layers and a non-homogeneous interfacial layer without the use of baffles. Methods are also disclosed to use a lower cost metallic source and an oxygen bleed to create alumina or tantalum oxide vapor, to use a tantalum oxide or an alumina ingot and a low pressure inert gas feed to direct the vapor clouds, to use pulsed evaporation from a secondary vapor source to create non-homogeneous multilayer coating on non-rotated substrates, to use an electric bias to direct the vapor clouds, and to use a mechanical system to direct the vapor clouds or move and position the article to be coated in the clouds.

Abstract: A thermal barrier coating for nickel based superalloy articles such as turbine engine vanes and blades that are exposed to high temperature gas is disclosed. The coating includes a columnar grained ceramic layer applied to a platinum modified Ni3Al gamma prime phase bond coat having a high purity alumina scale. The preferred composition of the bond coat is 5 to 16% by weight of aluminum, 5 to 25% by weight of platinum with the balance, at least 50% by weight, nickel. A method for making the bond coat is also disclosed.

Abstract: A carbon deposit inhibiting thermal barrier coating for an internal element or component in a gas turbine engine. Such coating includes a layer of thermal barrier material coated onto the surface of an engine component that will be exposed to the flow of burning engine gases. Such coating further includes a layer of carbon deposit inhibiting material coated on top of the layer of thermal barrier material.

Abstract: An electrolyte for use in electrolytic platinum plating that results in reduced Cl, S, or P contaminant production. The bath comprises 0.01 to 320 g/lit of platinum in the form of the platinum salt dinitrodiammine platinum, Pt(NH3)2(NO2)2 or variants thereof and 0.1 to 240 g/lit of alkali metal carbonate M2CO3 or bicarbonate MHCO3 where M is selected from a group comprising lithium (Li), sodium (Na), potassium (K), rubidium (Rb) and cesium (Cs). A method of improving oxidation resistance of a platinum modified aluminide diffusion coating on a substrate, comprises electroplating the substrate using this electrolyte and then aluminizing the electroplated substrate at an elevated temperature to grow a platinum modified aluminide diffusion coating.

Abstract: A thermal barrier coating for nickel based superalloy articles such as turbine engine vanes and blades that are exposed to high temperature gas is disclosed. The coating includes a columnar grained ceramic layer applied to a platinum modified Ni3Al gamma prime phase bond coat having a high purity alumina scale. The preferred composition of the bond coat is 5 to 16% by weight of aluminum, 5 to 25% by weight of platinum with the balance, at least 50% by weight, nickel. A method for making the bond coat is also disclosed.