There is disclosed herein processes and systems for forming fiber-reinforced ceramic composite structures which, contrary to conventional methods, directly deposit a ceramic fiber composite on a working surface. The processes and systems enable the printing of ceramic fiber composite structures having complex shapes and allow for multiple fiber-matrix material combinationsso far not possible with conventional approaches. In addition, the systems and process described herein enable the printing of ceramic fiber composites on complex 3D surfaces, such as gas turbine components.

A method of making a ceramic matrix composite (CMC) article by combining a preceramic polymer with one or more sized nanopowders and optional surfactants and/or solvents to form a mixture suitable for 3D printing, depositing the mixture on a mandrel, curing it to form a green body, and pyrolyzing the green body such that the nanocrystalline surface of the CMC article has sufficiently the same surface roughness and figure accuracy of the mandrel to enable the CMC article to be used without further polishing. The mixture can be a paste or slurry that is self supporting and exhibit pseudoplastic rheology. The preceramic polymer is preferably a precursor to SiC, and the nanopowders preferably comprise SiC. The article can be densified by using polymer infiltration pyrolysis, with or without nanoparticles. The curing and pyrolysis of the article can be performed with microwave radiation. An example structure is a gradient density lattice with a mirror surface for use in a cryogenically cooled infrared optical system such as an orbiting space telescope.

A segmented composite exhaust flue which may be used to shield an area or object from convective, conductive, or radiated heat transfer from hot exhaust combustion gases is described. In certain embodiments, the composite exhaust flue may be used to protect structures from hot exhaust gases and particles such as those produced by cars, trucks, ships, boats, jets, rockets, as well as other vehicles with internal combustion engines, turbines, or rocket motors. In some embodiments, a composite exhaust flue may include an attachment frame removeably holding a plurality of ceramic composite panels where the ceramic composite panels have a ceramic fiber reinforced ceramic composite high temperature face sheet positioned over an insulating layer.

The invention relates to sealing a fuel rod composite cladding tube composed of silicon carbide regardless of the fuel rod cladding design architecture (e.g., monolithic, duplex with monolithic SiC on the inside and a composite made with SiC fibers and SiC matrix on the outside) preferably with sealed SiC end plug caps, additionally sealed with an interior braze and exterior SiC final coating, thus providing a double sealed end plug barrier effective at retaining gas tightness and providing mechanical strength for the sealed end joint while providing high chemical resistance.

Various embodiments include a metal-repaired ceramic matrix composite (CMC) article, and a method of repairing a CMC article having a defect. Particular embodiments include a method including: removing a defect-containing portion of the CMC article; forming at least one opening in a remaining portion of the CMC article; preparing a metal repair preform for replacing at least the removed portion of the CMC article, wherein a portion of the metal repair preform complements the at least one opening; and attaching the metal repair preform to the remaining portion of the CMC article.

A method of preparing a ceramic matrix composite (CMC) component that includes a protective ceramic layer comprises adhering at least one flexible ceramic tape to a ceramic fiber preform, where the at least one flexible ceramic tape comprises ceramic particles dispersed in an organic binder phase. After the adhering, the at least one flexible ceramic tape is heated to a temperature sufficient to volatilize the organic binder phase, thereby forming a porous ceramic layer on at least a portion of the ceramic fiber preform. After the heating and volatilizing, the ceramic fiber preform and the porous ceramic layer are infiltrated with a molten material, thereby forming a CMC component including, on at least a portion thereof, a protective ceramic layer.

A ceramic bonding material including at least one fibrous material, a flux agent and a thickening agent wherein the ceramic bonding material fired at a set temperature to bond the two adjacent substrate faces.

The present invention concerns a shaped composite material and a method for producing it. More specifically, the invention concerns a disc for a disc brake made from ceramic composite materials, usually known as CMC, i.e. Carbon Material Ceramic or CCM, i.e. Carbon Ceramic Material. These materials consist of carbon matrices containing carbon fibres usually infiltrated with silicon and a product of reaction between C and Si, silicon carbide (SiC). More specifically, the invention concerns a shaped composite material comprising a inner layer (3; 103) of CCM C/SiC/Si material comprising disorderly short filaments consisting mainly of carbon and respective outer layers (2, 2; 102, 102) of C/SiC/Si material and having an orderly fabric structure of mainly carbon fibres.

A turbine component assembly is disclosed, including a first component, a second component, and an interface shield. The first component is arranged to be disposed adjacent to a hot gas path, and includes a ceramic matrix composite composition. The second component is adjacent to the first component and arranged to be disposed distal from the hot gas path across the first component. The interface shield is disposed on a contact region of the first component, and directly contacts the second component.

A ceramic bonding material including at least one fibrous material, a flux agent and a thickening agent wherein the ceramic bonding material fired at a set temperature to bond the two adjacent substrate faces.