A supporting substrate for a composite substrate comprises a ceramic and has a polished surface for use in bonding. An orientation degree of the ceramic forming the supporting substrate at the polished surface is 50% or higher, and an aspect ratio of each crystal grain included in the supporting substrate is 5.0 or less.

A method of making a fiber preform for ceramic matrix composite (CMC) fabrication comprises laminating an arrangement of fibers between polymer sheets comprising an organic polymer, which may function as a fugitive binder during fabrication, to form a flexible prepreg sheet. A plurality of the flexible prepreg sheets are laid up in a predetermined geometry to form a stack, and the stack is heated to soften the organic polymer and bond together the flexible prepreg sheets into a bonded prepreg structure. Upon cooling of the bonded prepreg structure, a rigid preform is formed. The rigid preform is heated at a sufficient temperature to pyrolyze the organic polymer. Thus, a porous preform that may undergo further processing into a CMC is formed.

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 porous ceramic particle includes a porous portion and a dense layer. The porous portion has a plate-like shape and a pair of main surfaces in parallel with each other. The dense layer has porosity lower than that of the porous portion and covers at least one main surface among the pair of main surfaces of the porous portion. A portion of a surface of the porous portion, which is other than the pair of main surfaces, is exposed from the dense layer. It is thereby possible to provide a porous ceramic particle of low thermal conductivity and low heat capacity.

A chassis defines a system housing that houses a processing system and a display system. A chassis wall provided on the chassis includes a first carbon fiber layer that provides an outer surface of the chassis that is located opposite the chassis wall from the housing and a ceramic layer that is bonded to the first carbon fiber layer and located opposite the first carbon fiber layer from the outer surface. The ceramic layer provides additional stiffness to the chassis wall to resist deflection of the chassis wall into at least one of the display system and the processing system in response to a force. The chassis wall may include a second carbon fiber layer that is bonded to the ceramic layer and located opposite the ceramic layer from the first carbon fiber layer to provide an inner surface of the chassis wall.

Anti-ballistic armor element, comprising a ceramic body comprising a sintered material consisting of ceramic grains with a Vickers hardness of more than 5 GPa, the total pore volume of said material being between 0.5 and 10%, said ceramic body being characterized in that the cumulative volume of pores with a diameter of between 30 and 100 micrometers represents between 0.2 and 2.5% of the volume of said material, the cumulative volume of pores with a diameter of more than 100 micrometers is less than 0.2% of the volume of said material , the remainder of said total pore volume consisting of pores whose diameter is less than 30 micrometers.

A method of assembling a composite panel includes disposing a pliable matrix material between a first side of a ceramic core structure and a ceramic matrix composite face sheet, wherein the ceramic core structure comprises a plurality of hollow cells defined by a plurality of walls extending from the first side of the ceramic core structure to a second side of the ceramic core structure opposite the first side; and densifying the pliable matrix material to bond the pliable matrix material with the ceramic core structure and the ceramic matrix composite face sheet.

A pre-stressed curved plate comprising a curved plate having at least one concave surface, the curved plate being enveloped and adhesively bonded with tensioned reinforcing fibers, whereby the reinforcing fibers are first wound around the plate under tension being spaced apart from the concave surface and subsequently subjected to pressure to stretch and bond the reinforcing fibers to the surfaces of the plate, where upon bonding, the tensile strain of the fiber introduces stress in the plate.

In some examples, a method including positioning a first ceramic or ceramic matrix composite (CMC) part and a second ceramic or CMC part adjacent to each other to define a joint between adjacent portions of the first ceramic or CMC part and the second ceramic or CMC part; and depositing an aqueous braze paste at least one of in the joint or adjacent the joint, wherein the aqueous braze paste comprises water, a water-soluble polymeric binder, and a silicon-based powder alloy.

A brake disc manufactured by a method of manufacturing a brake disc according to the present invention includes a carbon fiber Cf, silicon Si, silicon carbide Sic, and a silicon-copper alloy Si.sub.xCu.sub.y. The carbon fiber Cf, silicon Si, carbon C, and silicon carbide SiC make a disc light and provide high thermal shock resistance, anti-oxidation, wear resistance, strength, and friction coefficient. The copper Cu and silicon-copper alloy Si.sub.xCu.sub.y increase heat capacity at constant volume of a disc, so a large increase in temperature of the disc is prevented and a changing range of the friction coefficient is reduced in braking. Accordingly, the brake disc according to the present invention has all of the advantage of a brake disc made of a carbon fiber-reinforced ceramic composites without thermal deformation and deterioration of a pad, a hat part, and a caliper.