Abstract: An apparatus is disclosed including a first and second article, a first interface volume disposed between and enclosed by the first article and second article, a cooling fluid supply, and at least one cooling fluid channel in fluid communication with the cooling fluid supply and the first interface volume. The first article includes a first material composition. The second article includes a second material composition. The at least one cooling fluid channel includes a heat exchange portion disposed in at least one of the first and second article downstream of the cooling fluid supply and upstream of the first interface volume. A turbine shroud is disclosed wherein the first and second articles are an outer and inner shroud. A turbine nozzle is disclosed wherein the first and second articles are an endwall and fairing.

Abstract: A gas turbine blade may have a bond coat applied to its surface. A porous substrate may be applied to the bond layer and one or more protective layers may be applied to the bond layer such that the fiber mesh is embedded between the bond layer and the protective layer to prevent creep.

Abstract: A gas turbine seal assembly includes a gas turbine component and a gas turbine seal component contacting the gas turbine component to form a seal between the two components. The gas turbine seal component includes ceramic matrix composite plies bonded together to form the ceramic matrix composite component. A bond-inhibiting coating on a non-bonding portion of a first surface of one of the ceramic matrix composite plies prevents bonding between the non-bonding portion of the first surface and a second surface of a neighboring ceramic matrix composite ply. At least one bonding portion of the first surface lacking the bond-inhibiting coating is bonded to the second surface. A method of forming a ceramic matrix composite component includes selectively applying a bond-inhibiting coating to a non-bonding portion of a first surface of a ceramic matrix composite ply and bonding the ceramic matrix composite plies together.

Abstract: A method for treating a field operated component is disclosed which includes providing the component including a ceramic matrix composite and removing a first portion of the component, forming a first exposed surface on the component. The method further includes providing a second portion including the composite, the second portion having a second exposed surface including a conformation adapted to mate with the first exposed surface. The second portion is positioned in association with the component so as to replace the first portion, and the second portion and the component are joined to form a treated component. Another method is disclosed wherein the component is a turbine component which further includes removing an environmental barrier coating from the component, arranging and conforming the first exposed surface and the second exposed surface to define a joint, and applying an environmental barrier coating to the treated component.

Abstract: Components are disclosed which include a CMC substrate having a first surface and a second surface. The first surface is in fluid communication with a compressed, dry fluid, and the second surface is in fluid communication with a wet fluid stream and includes a hermetic coating. The components further include at least one opening extending from the first surface through a portion of the CMC substrate, wherein, upon removal of a fragment of one or both of the hermetic coating and the CMC substrate, the at least one opening selectively permits a flow of the compressed, dry fluid to the second surface. In one embodiment, the component is a gas turbine component, the wet fluid stream is a hot combustion stream, the hermetic coating is an environmental barrier coating, and the flow reduces or eliminates volatilization of the CMC substrate. Methods for forming the components are also disclosed.

Abstract: A process of producing a ceramic matrix composite gas turbine component and a ceramic matrix composite gas turbine component are provided. The process includes modifying a surface of the ceramic matrix composite gas turbine component to produce a modified surface with a surface roughness of less than 6 micrometers. The modifying is selected from the group of techniques consisting of applying unreinforced matrix plies to the surface, vapor depositing silicon on the surface, honing the surface, applying braze paste to the surface, and combinations thereof. The component includes a modified surface including a surface roughness of less than 6 micrometers. The modified surface being selected from the group consisting of unreinforced matrix plies applied to a surface of the ceramic matrix composite gas turbine component, silicon vapor deposited on the surface, a honed surface, a braze paste applied to the surface, and combinations thereof.

Abstract: A turbine component, a turbine blade, and a turbine component fabrication process are disclosed. The turbine component includes ceramic matrix composite plies and a feature configured for preventing interlaminar tension of the ceramic matrix composite plies. The feature is selected from the group consisting of ceramic matrix composite tows or precast insert tows extending through at least a portion of the ceramic matrix composite plies, a woven fabric having fiber tows or a precast insert preventing contact between a first set of the ceramic matrix composite plies and a second set of the ceramic matrix composite plies, and combinations thereof. The process includes laying up ceramic matrix composite plies in a preselected arrangement and securing a feature configured for interlaminar tension.

Abstract: A method for treating a field operated component is disclosed which includes providing the component including a ceramic matrix composite and removing a first portion of the component, forming a first exposed surface on the component. The method further includes providing a second portion including the composite, the second portion having a second exposed surface including a conformation adapted to mate with the first exposed surface. The second portion is positioned in association with the component so as to replace the first portion, and the second portion and the component are joined to form a treated component. Another method is disclosed wherein the component is a turbine component which further includes removing an environmental barrier coating from the component, arranging and conforming the first exposed surface and the second exposed surface to define a joint, and applying an environmental barrier coating to the treated component.

Abstract: An apparatus to reduce wear and friction between CMC-to-metal attachment and interface, including a metal layer configured for insertion between a surface interface between a CMC component and a metal component. The surface interface of the metal layer is compliant relative to asperities of the surface interface of the CMC component. A coefficient of friction between the surface interface of the CMC component and the metal component is about 1.0 or less at an operating temperature between about 300° C. to about 325° C. and a limiting temperature of the metal component.

Abstract: An apparatus having reduced wear and friction between CMC-to-metal attachment and interface of the apparatus, including a CMC component having a surface. The CMC component surface is configured for sliding contact with a surface of a metal component, the sliding contact resulting in formation of debris along the contacting surfaces. The surface of the CMC component has an engineered surface feature formed therein to substantially prevent an accumulation of debris along the contacting surfaces.

Abstract: Components are disclosed which include a CMC substrate having a first surface and a second surface. The first surface is in fluid communication with a compressed, dry fluid, and the second surface is in fluid communication with a wet fluid stream and includes a hermetic coating. The components further include at least one opening extending from the first surface through a portion of the CMC substrate, wherein, upon removal of a fragment of one or both of the hermetic coating and the CMC substrate, the at least one opening selectively permits a flow of the compressed, dry fluid to the second surface. In one embodiment, the component is a gas turbine component, the wet fluid stream is a hot combustion stream, the hermetic coating is an environmental barrier coating, and the flow reduces or eliminates volatilization of the CMC substrate. Methods for forming the components are also disclosed.

Abstract: An assembly and method for affixing a turbomachine rotor blade to a rotor wheel are disclosed. In an embodiment, an adaptor member is provided disposed between the blade and the rotor wheel, the adaptor member including an adaptor attachment slot that is complementary to the blade attachment member, and an adaptor attachment member that is complementary to the rotor wheel attachment slot. A coverplate is provided, having a coverplate attachment member that is complementary to the rotor wheel attachment slot, and a hook for engaging the adaptor member. When assembled, the coverplate member matingly engages with the adaptor member, and retains the blade in the adaptor member, and the assembly in the rotor wheel.

Abstract: An apparatus having reduced wear and friction between CMC-to-metal attachment and interface of the apparatus, including a CMC component having a surface. The CMC component surface is configured for sliding contact with a surface of a metal component, the sliding contact resulting in formation of debris along the contacting surfaces. The surface of the CMC component has an engineered surface feature formed therein to substantially prevent an accumulation of debris along the contacting surfaces.

Abstract: An assembly and method for affixing a turbomachine rotor blade to a rotor wheel are disclosed. In an embodiment, an adaptor member is provided disposed between the blade and the rotor wheel, the adaptor member including an adaptor attachment slot that is complementary to the blade attachment member, and an adaptor attachment member that is complementary to the rotor wheel attachment slot. A coverplate is provided, having a coverplate attachment member that is complementary to the rotor wheel attachment slot, and a hook for engaging the adaptor member. When assembled, the coverplate member matingly engages with the adaptor member, and retains the blade in the adaptor member, and the assembly in the rotor wheel.

Abstract: An apparatus having reduced wear and friction between CMC-to-metal attachment and interface of the apparatus, including a CMC component having a surface. The CMC component surface is configured for sliding contact with a surface of a metal component, the sliding contact resulting in formation of debris along the contacting surfaces. The surface of the CMC component has an engineered surface feature formed therein to substantially prevent an accumulation of debris along the contacting surfaces.

Abstract: In an embodiment, a system includes a turbomachine having a first turbomachine component including a first mechanoluminescent material. The first turbomachine component is configured to produce a first light emission upon exposure to a mechanical stimulus sufficient to cause mechanoluminescence by the first mechanoluminescent material. The system also includes a turbomachine monitoring system configured to monitor the structural health of the first component based on detection of the first light emission.

Abstract: A turbine bucket assembly and turbine system are disclosed. The turbine bucket assembly includes a single-lobe joint having an integral platform, the joint having a first axial length; a non-segmented airfoil having a root section and a tip section integral with the root section, the tip section having a tip end with a second axial length, the second axial length being less than the first axial length; and a turbine wheel having a receptacle with a geometry corresponding to the single-lobe joint and being coupled to the single-lobe joint. The turbine wheel includes a turbine wheel material and the single-lobe joint and the non-segmented airfoil include a turbine bucket material, the turbine bucket material having a higher heat resistance and a lower thermal expansion than the turbine wheel material.

Abstract: A process of producing a ceramic matrix composite gas turbine component and a ceramic matrix composite gas turbine component are provided. The process includes modifying a surface of the ceramic matrix composite gas turbine component to produce a modified surface with a surface roughness of less than 6 micrometers. The modifying is selected from the group of techniques consisting of applying unreinforced matrix plies to the surface, vapor depositing silicon on the surface, honing the surface, applying braze paste to the surface, and combinations thereof. The component includes a modified surface including a surface roughness of less than 6 micrometers. The modified surface being selected from the group consisting of unreinforced matrix plies applied to a surface of the ceramic matrix composite gas turbine component, silicon vapor deposited on the surface, a honed surface, a braze paste applied to the surface, and combinations thereof.

Abstract: A turbine repair process, a repaired coating, and a repaired turbine component are disclosed. The turbine repair process includes providing a turbine component having a higher-pressure region and a lower-pressure region, introducing particles into the higher-pressure region, and at least partially repairing an opening between the higher-pressure region and the lower-pressure region with at least one of the particles to form a repaired turbine component. The repaired coating includes a silicon material, a ceramic matrix composite material, and a repaired region having the silicon material deposited on and surrounded by the ceramic matrix composite material. The repaired turbine component a ceramic matrix composite layer and a repaired region having silicon material deposited on and surrounded by the ceramic matrix composite material.

Abstract: A pre-form CMC cavity and method of forming pre-form CMC cavity for a ceramic matrix component includes providing a mandrel, applying a base ply to the mandrel, laying-up at least one CMC ply on the base ply, removing the mandrel, and densifying the base ply and the at least one CMC ply. The remaining densified base ply and at least one CMC ply form a ceramic matrix component having a desired geometry and a cavity formed therein. Also provided is a method of forming a CMC component.