A reinforced composite structure is disclosed comprising a heat resistant chemically-bonded layer of a ceramic composition mechanically attached to a metallic substrate. The structure includes a metallic anchoring matrix characterized by a plurality of spatially and cooperably arranged reinforcing elements, the matrix being attached to the substrate and projecting from the surface thereof with the spatially arranged reinforcing elements of the matrix collectively defining a ceramic-occupiable zone of finite thickness adjacent to and following the surface configuration of said substrate, the zone having at least confined therein the heat resistant chemically-bonded ceramic in intimate contact with the reinforcing elements. A method for fabricating said composite structure is also disclosed.

Ceramic-metal composites

A ceramic composition for insulating components, made of ceramic matrix composites, of gas turbines is provided. The composition comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere and the arrangement of spheres is such that the composition is dimensionally stable and chemically stable at a temperature of approximately 1600 °C. A stationary vane of a gas turbine comprising the composition of the present invention bonded to the outer surface of the vane is provided. A combustor comprising the composition bonded to the inner surface of the combustor is provided. A transition duct comprising the insulating coating bonded to the inner surface of the transition is provided. Because of abradable properties of the composition, a gas turbine blade tip seal comprising the composition also is provided. The composition is bonded to the inside surface of a shroud so that a blade tip carves grooves in the composition so as to create a customized seal for the turbine blade tip.

Use of high temperature insulation for ceramic matrix composites in gas turbines

A segmented abradable ceramic coating system having superior abradability and erosion resistance is disclosed. The system includes a duct segment having a metallic substrate, a MCrAlY bond coat on the substrate and a segmented abradable ceramic coating on the bond coat. The segmented abradable ceramic coating includes a base coat foundation layer, a graded interlayer and an abradable top layer for an overall thickness of preferably about 50 mils (1.270 mm). The coating is characterized by a plurality of vertical microcracks. By precisely controlling the deposition parameters, composition of the layers and layer particle morphology, segmentation is achieved, as well as superior abradability and erosion resistance.

Segmented abradable ceramic coating

A composite thermal barrier coating system includes a honeycomb metallic structure (2) filled with high thermal expansion ceramic hollow spheres (6) in a phosphate bonded matrix. The composite thermal barrier coating system may be manufactured to thicknesses (T) in excess of current thermal barrier coating systems, thereby imparting greater thermal protection. Superior erosion resistance and abrasion properties are also achieved. The composite thermal barrier coating is useful on combustion turbine components such as ring seal segments, vane segment shrouds, transitions and combustors.

High temperature erosion resistant, abradable thermal barrier composite coating

A ceramic composition is provided to insulate ceramic matrix composites under high temperature, high heat flux environments. The composition comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere. The spheres may be any combination of Mullite spheres, Alumina spheres, or stabilized Zirconia spheres. The filler powder may be any combination of Alumina, Mullite, Ceria, or Hafnia. Preferably, the phosphate binder is Aluminum Ortho-Phosphate. A method of manufacturing the ceramic insulating composition and its application to CMC substrates are also provided.

High temperature insulation for ceramic matrix composites

A thermal turbomachine casing having a multilayer heat insulation liner including a metallic bond coat in direct contact with the casing wall, a ceramic heat insulation layer bonded to the bond coat, and preferably an abradable coating in the form of a porous, predominantly metallic, top layer bonded to the ceramic layer. A metallic honeycomb may be fixed to the casing wall, in which case the bond coat, ceramic layer, and top layer are within the cells of the honeycomb. The bond coat and ceramic layer may partially or completely fill the honeycomb cells. The layers may be deposited by flame or plasma spraying, preferably after peening the casing wall. Each succeeding layer is deposited before any cooling of the preceeding layer.

Casing for a thermal turbomachine having a heat-insulating liner

A.CARTER DE TURBO-MACHINE THERMIQUE A REVETEMENT ISOLANT THERMIQUE. B.CARTER CARACTERISE EN CE QUE LE REVETEMENT SE COMPOSE D'UNE COUCHE D'ACCROCHAGE OU DE COLLAGE METALLIQUE 31 REVETUE D'UNE COUCHE INTERMEDIAIRE 32 EN MATIERE CERAMIQUE, ELLE-MEME REVETUE D'UNE COUCHE DE REVETEMENT POREUSE 33 PRINCIPALEMENT METALLIQUE. C.L'INVENTION CONCERNE LE REVETEMENT DU CARTER DE TURBO-MACHINES.

Gunter Albrecht

Papers

Casing for a thermal turbomachine having a heat-insulating liner

Carter de turbo-machine thermique a revetement isolant thermique