Adhesive compositions and methods for bonding materials with different thermal expansion coefficients is provided. The adhesive is formulated using a flux material, a low flux material, and a filler material, where the filler material comprises particulate from at least one of the two components being bonded together. A thickening agent can also be used as part of the adhesive composition to aid in applying the adhesive and establishing a desired bond thickness. The method of forming a high strength bond using the disclosed adhesive does not require the use of intermediary layer or the use of high cure temperatures that could damage one or both of the components being bonded together.

A fiber reinforced composite component may include interleaved fiber layers and ceramic particle layers coated with matrix material. The fiber reinforced composite component may be fabricated by forming a fibrous preform, needling the fibrous preform to form a plurality of z-direction fibers, and densifying the fibrous preform. The fibrous preform may be fabricated by forming a first ceramic particle layer over a first fiber layer, disposing a second fiber layer over the first ceramic particle layer, forming a second ceramic particle layer over the second fiber layer, and disposing a third fiber layer over the second ceramic particle layer.

A method of producing a ceramic matrix composite including a protective ceramic coating thereon comprises applying a surface slurry onto an outer surface of an impregnated fiber preform. The surface slurry includes particulate ceramic solids dispersed in a flowable preceramic polymer comprising silicon, and the impregnated fiber preform comprises a framework of ceramic fibers loaded with particulate matter. The flowable preceramic polymer is cured, thereby forming on the outer surface a composite layer comprising a cured preceramic polymer with the particulate ceramic solids dispersed therein. The cured preceramic polymer is then pyrolyzed to form a porous ceramic layer comprising silicon carbide, and the impregnated fiber preform and the porous ceramic layer are infiltrated with a molten material comprising silicon. After infiltration, the molten material is cooled to form a ceramic matrix composite body with a protective ceramic coating thereon.

A laminate composite structure having at least one tubular region and at least one bonded region. The structure has a first composite layer, a second composite layer, a cavity, and one or more reinforcing fibers. Each composite layer comprises composite material with a top face and a bottom face opposite the top face. The top face of one is joined to the bottom face of the other along an interlaminar region. The cavity separates the bottom face and the top face to form a tube. The tube has an internal boundary defined by the bottom face and the top face. The reinforcing fibers line the internal boundary and are arranged so that the reinforcing fibers reduce the propensity of the composites layer to separate under internal pressure loading.

A method of forming an integral fastener for a ceramic matrix composite component comprises the steps of forming a fiber preform with an opening, forming a fiber fastener, inserting the fiber fastener into the opening, and infiltrating a matrix material into the fiber preform and fiber fastener to form a ceramic matrix composite component with an integral fastener. A gas turbine engine is also disclosed.

A gas turbine engine component includes a gas turbine engine component body formed of a ceramic matrix composite material having at least one fastener integrally formed with the gas turbine engine component body as a single-piece structure. The gas turbine engine component body initially comprises a rigidized preform structure formed from a polymer based material. The at least one fastener connects the gas turbine engine component body to an engine support structure.

A method of forming an integral fastener for a ceramic matrix composite component comprises the steps of forming a fiber preform with an opening, forming a fiber fastener, inserting the fiber fastener into the opening, and infiltrating a matrix material into the fiber preform and fiber fastener to form a ceramic matrix composite component with an integral fastener. A gas turbine engine is also disclosed.

A hollow CMC article, a mandrel for forming the article and a method for forming the article are disclosed. The article includes a ply-wrap layer defining a cavity. The ply-wrap layer includes a first face, a second face, a root portion bridging the faces, and a plurality of CMC wrap plies. The root portion defines a terminus of the ply-wrap layer including a cross-sectional conformation consisting of a curve having a single turning point. Each of the plurality of CMC wrap plies are disposed along the first face, wrap over the root portion, and extend along the second face. The hollow article further includes a plurality of CMC lateral plies disposed along the faces.

Methods of producing a carbon matrix composite are provided which include preparing a carbon matrix composite precursor comprising at least one carbon-based reinforcement material and a cured thermoset polymer matrix comprising a chemical composition in accordance with Formula I ##STR00001##
where n and m are integers, at least one of R.sup.1 or R.sup.2 comprises an aromatic moiety, and X is selected from the group consisting of CH.sub.2, NH, O, S, SO.sub.2, and combinations thereof. The methods further include heating the carbon matrix composite precursor in air to a first processing temperature of between 300° C. and 500° C. to form a carbon matrix composite intermediate, and heating the carbon matrix composite intermediate in nitrogen to a second processing temperature of between 900° C. to 1650° C. and holding at the second processing temperature for at least 1 hour in an inert gas environment to form the carbon matrix composite.

An airfoil includes a ceramic matrix composite airfoil core that defines an airfoil portion and a root portion. The ceramic matrix composite airfoil core is subject to core thermal growth. A platform includes a ceramic matrix composite that wraps around the root portion. The platform is subject to platform thermal growth. A buffer layer is located between the root portion and the platform. The buffer layer absorbs a mismatch between the core thermal growth and the platform thermal growth.