Abstract: In accordance with an embodiment of the invention, an article is provided. The article comprises a substrate comprised of silicon containing material, an environmental barrier coating (EBC) overlying the substrate and a thermal barrier coating (TBC) on the environmental barrier coating. The thermal barrier coating comprising a compound having a rhombohedral phase.

Abstract: In accordance with an embodiment of the invention, a thermal barrier coating for inclusion in a thermal barrier coating system is provided. The thermal barrier coating comprises a compound having a rhombohedral phase. In accordance with another embodiment of the invention, a thermal barrier coating is provided that comprises a compound having the formula of: A4B3O12, wherein A is at least one rare earth element; and B is selected from the group consisting of Zr, Hf and mixtures thereof.

Abstract: A thermal barrier coating (TBC) for a component intended for use in a hostile environment, such as a component of a gas turbine engine. The TBC exhibits improved impact and erosion resistance as a result of being a composite material consisting essentially of particles of a ceramic reinforcement material dispersed in a ceramic matrix material. The ceramic reinforcement material has a yield strength greater than the ceramic matrix material at about 1100° C., and the particles of the ceramic reinforcement material have an average maximum dimension of greater than five micrometers.

Abstract: A ceramic material suitable for use as a coating, such as a porous thermal barrier coating (TBC) on a component intended for use in a hostile thermal environments. The coating material consists essentially of zirconia stabilized by at least one rare-earth metal oxide and further alloyed to contain a limited amount of titania. Rare-earth metal oxides of particular interest are lanthana, ceria, neodymia, europia, gadolinia, erbia, dysprosia, and ytterbia, individually or in combination. Zirconia, the rare-earth metal oxide, and titania are present in the coating material in amounts to yield a predominantly tetragonal phase crystal structure. The amount of titania in the coating is tailored to allow higher levels of stabilizer while maintaining the tetragonal phase, i.e., avoiding the cubic (fluorite) phase.

Abstract: A coating process and system suitable for use on components subjected to high temperatures. The coating system includes an overlay coating of predominantly B2 phase rhodium aluminide (RhAl) intermetallic compound containing about 25 to about 90 atomic percent rhodium, about 10 to about 60 atomic percent aluminum, optionally up to a combined total of about 25 atomic percent of one or more platinum group metals chosen from the group consisting of platinum, palladium, ruthenium, and iridium, and up to about 20 atomic percent of the base metal and alloying constituents of the substrate. The RhAl intermetallic coating may serve as an environmental coating, a diffusion barrier layer for an overlying environmental coating, or both, with or without an outer ceramic coating.

Abstract: Nb—Si based alloy articles comprising a Nb—Si based alloy upon which is disposed an environmentally-resistant coating are described. They include a coating comprising at least one phase selected from the group consisting of M(Al,Si)3, M5(Al,Si)3, and M3Si5Al2, wherein M is one or more of Nb, Ti, Hf, Cr. Such coating can improve the environmental (e.g., in oxidation-promoting environments) resistance of a Nb—Si based alloy and alloy articles. Methods for preparing these articles are described as well.

Abstract: In accordance with an embodiment of the invention, a thermal barrier coating for inclusion in a thermal barrier coating system is provided. The thermal barrier coating comprises a compound having a rhombohedral phase. In accordance with another embodiment of the invention, a thermal barrier coating is provided that comprises a compound having the formula of: A4B3O12, wherein A is at least one rare earth element; and B is selected from the group consisting of Zr, Hf and mixtures thereof.

Abstract: A turbine engine rotor component, such as a compressor or turbine disk or seal element, is protected from corrosion by implanting aluminum or chromium ions, or mixtures thereof, on the surface of the component. Additional metal ions, such as rare earth and reactive elements, may also be implanted on the surface of the component. The component may be heated in a nonoxidizing atmosphere at a specified temperature and time to diffuse the ions into the surface. The component is typically then heated or maintained at an elevated temperature in the presence of oxygen to form an oxide coating on the surface of the component.

Abstract: A coating process and system suitable for use on components subjected to high temperatures. The coating system includes an overlay coating of predominantly B2 phase rhodium aluminide (RhAl) intermetallic compound containing about 25 to about 90 atomic percent rhodium, about 10 to about 60 atomic percent aluminum, optionally up to a combined total of about 25 atomic percent of one or more platinum group metals chosen from the group consisting of platinum, palladium, ruthenium, and iridium, and up to about 20 atomic percent of the base metal and alloying constituents of the substrate. The RhAl intermetallic coating may serve as an environmental coating, a diffusion barrier layer for an overlying environmental coating, or both, with or without an outer ceramic coating.

Abstract: In accordance with an embodiment of the invention, a thermal barrier coating for inclusion in a thermal barrier coating system is provided. The thermal barrier coating comprises a compound having a rhombohedral phase. In accordance with another embodiment of the invention, a thermal barrier coating is provided that comprises a compound having the formula of: A4B3O12, wherein A is at least one rare earth element; and B is selected from the group consisting of Zr, Hf and mixtures thereof.

Abstract: In accordance with an embodiment of the invention, an article is provided. The article comprises a substrate comprised of silicon containing material, an environmental barrier coating (EBC) overlying the substrate and a thermal barrier coating (TBC) on the environmental barrier coating. The thermal barrier coating comprising a compound having a rhombohedral phase.

Abstract: An apparatus for depositing a ceramic coating on a component. The apparatus includes an evaporation source containing multiple different oxide compounds, at least one of the oxide compounds having a vapor pressure that is higher than the remaining oxide compounds, to deposit on the component a coating of the multiple oxide compounds. The apparatus further includes a device for introducing the evaporation source into a coating chamber, a device for suspending the component near the evaporation source, a device for projecting a high-energy beam on the evaporation source to melt and form a vapor cloud of the oxide compounds of the evaporation source, a device capable of preventing the vapor cloud from contacting and condensing on the component, and a device for moving the preventing device to allow the vapor cloud to contact and condense on the component.

Abstract: Niobium silicide articles are described. They include a surface region enriched with at least about 25 atom % germanium, which can enhance the properties of the article. Methods for preparing these articles are described as well. According to one method, an article is formed from a niobium silicide composite material which contains a selected amount of germanium. The article is then heat-treated under conditions sufficient to increase the level of germanium in the surface region to at least about 25 atom %, based on the total composition of the surface region. In another embodiment, a germanium-containing material is applied over a niobium-silicide article, and then diffused into the surface region of the article by way of a heat treatment.

Abstract: A gas turbine engine component and coating system including a superalloy substrate having a coating system disposed thereon. A bond coating may be applied to the substrate. An adherent layer of ceramic material forming a thermal barrier coating is present on the bond coat layer. A topcoat layer overlies the thermal barrier coating. The topcoat layer includes greater than about 20 wt % yttria.

Abstract: A coating process and system suitable for use on components subjected to high temperatures. The coating system includes an overlay coating of predominantly B2 phase rhodium aluminide (RhAl) intermetallic compound containing about 25 to about 90 atomic percent rhodium, about 10 to about 60 atomic percent aluminum, optionally up to a combined total of about 25 atomic percent of one or more platinum group metals chosen from the group consisting of platinum, palladium, ruthenium, and iridium, and up to about 20 atomic percent of the base metal and alloying constituents of the substrate. The RhAl intermetallic coating may serve as an environmental coating, a diffusion barrier layer for an overlying environmental coating, or both, with or without an outer ceramic coating.

Abstract: A coating process and system for an article having a substrate formed of a metal alloy that is prone to the formation of a secondary reaction zone (SRZ). The coating system includes an aluminum-containing overlay coating and a stabilizing layer between the overlay coating and the substrate. The overlay coating contains aluminum in an amount greater by atomic percent than the metal alloy of the substrate, such that there is a tendency for aluminum to diffuse from the overlay coating into the substrate. The stabilizing layer is predominantly or entirely formed of at least one platinum group metal (PGM), namely, platinum, rhodium, iridium, and/or palladium. The stabilizing layer is sufficient to inhibit diffusion of aluminum from the overlay coating into the substrate so that the substrate remains essentially free of an SRZ that would be deleterious to the mechanical properties of the alloy.

Abstract: A protected article has a substrate and a protective structure overlying a surface of the substrate. The protective structure includes a protective layer overlying the surface of the substrate and having an aluminum content greater than that of the substrate, and a bond-coat layer of a bond-coat-layer metal. The bond-coat-layer metal has a bond-coat initial composition having at least about 60 percent by weight platinum, rhodium, palladium, or combinations thereof. There may be a diffusion-barrier layer between the surface of the substrate and the protective layer, and there may be a ceramic thermal barrier coating overlying the bond-coat layer.

Abstract: A ceramic material suitable for use as a coating, such as a porous thermal barrier coating (TBC) on a component intended for use in a hostile thermal environments. The coating material consists essentially of zirconia stabilized by at least one rare-earth metal oxide and further alloyed to contain a limited amount of titania. Rare-earth metal oxides of particular interest are lanthana, ceria, neodymia, europia, gadolinia, erbia, dysprosia, and ytterbia, individually or in combination. Zirconia, the rare-earth metal oxide, and titania are present in the coating material in amounts to yield a predominantly tetragonal phase crystal structure. The amount of titania in the coating is tailored to allow higher levels of stabilizer while maintaining the tetragonal phase, i.e., avoiding the cubic (fluorite) phase.

Abstract: According to an embodiment of the invention, a repaired component is disclosed. The repaired component comprises an engine run component having a base metal substrate, a portion of the base metal substrate between about 1-3 mils in thickness and an overlying bond coat having been removed to create a remaining base metal substrate of reduced thickness. The repaired component further comprises a lower growth environmental bond coating comprising an alloy having an aluminum content of about 10-60 atomic percent applied to the remaining base metal substrate so that upon subsequent repair of the component, less than about 1-3 mils in thickness of the remaining base metal substrate is removed because of less environmental coating growth into the substrate than the prior bond coat. Advantageously, the repaired component has extended component life and increased repairability.

Abstract: In accordance with an embodiment of the invention, an article is provided. The article comprises a substrate comprised of silicon containing material, an environmental barrier coating (EBC) overlying the substrate and a thermal barrier coating (TBC) on the environmental barrier coating. The thermal barrier coating comprising a compound having a rhombohedral phase.