A technique of forming a carbon-carbon composite that includes infiltrating a preform comprising carbon fibers or carbon-precursor fibers with a pitch and pyrolyzing the pitch using a controlled pressure and temperature ramp rate to control a growth of optical textures as the pitch is pyrolyzed to a coke matrix. Pyrolyzing the pitch may include initiating pyrolysis of at least some of the pitch at a first pressure less than about 2000 psi and a first temperature ramp rate between about 5 ° C./hr and about 50 ° C./hr to a first target temperature, and pyrolyzing at least some of the pitch at a second pressure greater than 2000 psi and a second temperature ramp rate between about 5 ° C./hr and about 50 ° C./hr to a second target temperature, where the second target temperature is greater than the first target temperature.

A composite for a lithium air battery, wherein the composite is represented by Formula 1:
MC.sub.xN.sub.(1−x)  Formula 1 wherein M in Formula 1 is at least one selected from a metal element and a metalloid element, and 0<x<1.

A method for producing a three-dimensionally shaped object by stacking layers includes forming each layer using a three-dimensional shape composition containing particles, measuring the thickness of the layer, and ejecting onto the layer a liquid binder containing a binding agent capable of binding the particles. For the ejecting, the amount of the liquid binder to be ejected per unit area of the layer when viewed from above is adjusted according to the result of the measuring.

A self-lubricating flexible carbon composite seal includes an annular body formed from a flexible carbon composite.

A nitrogen-containing porous carbon material, and a capacitor and a manufacturing method thereof are provided. A carbon material, a macromolecular material and a modified material are mixed into a preform. The modified material includes nitrogen. A formation process is performed on the preform to obtain a formed object. High-temperature sintering is performed on the formed object to decompose and remove a part of the macromolecular material, while the other part of the macromolecular material and the carbon material together form a backbone structure including a plurality of pores. As such, the nitrogen becomes attached to the backbone structure to form a hydrogen-containing functional group to further obtain the nitrogen-containing porous carbon material. The nitrogen-containing porous carbon material may form a first nitrogen-containing porous carbon plate and a second nitrogen-containing porous carbon plate, which are placed in seawater to form a storage capacitor for seawater.

A method for producing a form-stable phase-change material includes freezing a slurry of solid and solvent to provide a frozen slurry, exposing the frozen slurry to conditions causing sublimation of the frozen solvent to remove solvent and provide a body having vacancies therein, sintering the body to provide a scaffold, and adding a molten phase-change material to the scaffold to provide the form-stable phase-change material. The same scaffold when ground acts as a phase-change nucleating aid.

A method for producing a silicon carbide sintered body, comprising adding water to a raw material mixture containing silicon carbide powder, at least one binder, and optionally at least one carbon source other than the silicon carbide and the at least one binder, and subjecting the raw material mixture to kneading, molding, and drying in this order, to obtain a dried body; heating the dried body to remove organic substances from the dried body to obtain a degreased body; and firing the degreased body in an inert atmosphere to obtain a silicon carbide sintered body. The method comprises controlling an expansion/shrinkage rate of the sintered body by adjusting at least one of (1) an amount of the at least one carbon source in the raw material mixture, (2) an amount of the at least one binder in the raw material mixture, and (3) a degreasing rate.

A method of forming a ceramic matrix composite (CMC) component having an engineered surface includes applying a surface slurry comprising first particulate solids in a liquid carrier to an outer surface of a ceramic fiber preform. The surface slurry is dried to remove the liquid carrier, and thus a surface slurry layer comprising the first particulate solids is formed on the outer surface. The surface slurry layer is polished to a predetermined thickness and/or surface finish. After polishing, a ceramic tape comprising second particulate solids is applied to the surface slurry layer, and pressure is applied to attach the ceramic tape to the surface slurry layer and to induce consolidation of the ceramic tape and the surface slurry layer. Thus, a multilayer surface region comprising the surface slurry layer and a ceramic tape layer is formed on the ceramic fiber preform. The ceramic fiber preform and the multilayer surface region are infiltrated with a molten material, and, upon cooling, a CMC component having an engineered surface is formed.

The disclosure describes a method for forming a surface layer of a ceramic matrix composite (CMC) article. The technique includes depositing a slurry on a surface of an infiltrated CMC. The slurry includes a carrier material, a binder, a plasticizer, and solid particles. The solid particles include a plurality of fine ceramic particles defining a fine particle average size less than about 5 micrometers. The method further includes drying the slurry to form an article having an outer surface layer that includes the solid particles on the infiltrated CMC. The method further includes machining at least a portion of the outer surface layer of the article. The method further includes infiltrating the article with a molten infiltrant to form a composite article.

A system and method for forming a porous ceramic preform is provided. The method may include forming a stacked powder structure including a binder layer and a powder layer on the binder layer. The binder layer may be formed by depositing a binder with a spray nozzle on a substrate. The powder layer may be formed by depositing a powder on the binder layer. The porous ceramic preform may be formed by heating the stacked powder structure to pyrolyze the binder. The porous ceramic preform is configured to be infiltrated by a molten material. The substrate may comprise a ceramic fiber preform. After melt infiltration of the porous ceramic preform and the ceramic fiber preform, a densified ceramic feature having a predetermined geometry may be formed on a ceramic matrix composite (CMC) component.