A composite material, compositions, processes and methods of using coal and coal by-products composite ceramics is provided for use as a safe, non-toxic material for construction, building and architecture components. The composite material disclosed herein is formed from resin/coal aggregates that contain and prevent the release of harmful impurities that naturally occur in both coal and coal by-products while the advantages of coal-based composites are made available to the building industry. The strength, density and porosity of the composites can be tailored within a wide range to fit the final application by controlling the materials, form factor and processing parameters during fabrication.

A fiber reinforced composite component may include interleaved textile layers and ceramic particle layers coated with matrix material. The fiber reinforced composite component may be fabricated by forming a fibrous preform and densifying the fibrous preform. The fibrous preform may be fabricated by performing a silicon melt infiltration after the densification process. A plurality of pores defined by the carbon matrix material are infiltrated with a silicon material and the fibrous preform is heated to a melt temperature until a desired percentage (e.g., at least 50%) of the carbon matrix material is converted into silicon carbide or another oxidation resistant material.

Disclosed are a high-entropy nitride ceramic fiber, and a preparation method and use thereof. The high-entropy ceramic fiber comprises Ti, Hf, Ta, Nb, and Mo; the high-entropy nitride ceramic fiber presents single crystal phase, and each of the elements are uniformly distributed at molecular level. The preparation method of the high-entropy ceramic fiber comprises: mixing a high-entropy ceramic precursor comprising the target metal elements, a spinning aid, and a solvent uniformly to prepare a precursor spinning solution, followed by working procedures of spinning, pyrolyzation, and nitriding to prepare the high-entropy nitride ceramic fiber. The high-entropy nitride ceramic fiber can be used in photocatalysis process of carbon dioxide to prepare methane.

A marking system includes a composition having at least one color precursor, a moldable substrate having a color developer, and a marking instrument for applying the composition to the moldable substrate to form at least one mark on the moldable substrate. A method of producing a colored three-dimensional molded object includes the steps of manipulating a moldable substrate having a color developer into a molded shape having an outer surface; and applying, on the outer surface of the molded shape, a first composition having at least one color precursor to a first portion of the molded shape.

The disclosure relates to methods of fabricating of ceramic structures, and more particularly to methods of fabricating ceramic structures having profiled surfaces and more particularly to methods of fabrication of ceramic mirror blanks. In one embodiment, a method of forming a shaped ceramic article, includes: forming, via one of a cold-pressing process or pressure casting process, a green ceramic article comprising a first surface, an opposing second surface and at least one high aspect ratio feature shaped into at least one surface; heating the green featured ceramic part to form a debound featured ceramic part; and densifying the debound featured ceramic part via one of a pressureless sintering process or a hot-pressing process.

The present application relates to a magnesium oxide based dielectric ceramics with ultrahigh dielectric breakdown strength and a preparation method thereof. The composition of the magnesium oxide based dielectric ceramic material comprises: (1−x)MgO—xAl.sub.2O.sub.3, wherein 0<x≤0.12 and x is a mole percentage. The material has a specific composite structure with magnesium aluminate spinel acting as a second phase surrounding a principal crystalline phase, MgO.

A graphite-containing refractory has higher bending strength and fracture energy than known refractories. The graphite-containing refractory has a graphite content of 1% to 80% by mass. 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 μm/fiber are bundled. The carbon fiber bundle has a length of 100 mm or more and is placed within the graphite-containing refractory to form the same.

A method of fabricating a carbon-carbon composite includes mixing a carbon-based matrix precursor with a carbon nanomaterial additive forming a polymeric matrix impregnated with the carbon nanomaterial additive, heating the impregnated polymeric matrix under an inert atmosphere, with temperatures ranging between 350-1100° C. for carbonization followed by graphitization at a temperature greater than 1800° C. The matrix precursor may be a graphitizing or non-graphitizing material. The additive may present basal or edge site carbon atoms or a combination of both. As a result, a carbon-carbon composite composed of the matrix and additive is formed by templating or bond formation, wherein at least 1-D nano-scale or micro-scale structural changes begins at the interface between the matrix and additive and propagates outward from the interface into the matrix, thus adjusting or altering the nano- or micro-structures in the matrix that would not naturally occur in the absence of the additive.

A method of producing a graphite-containing refractory within which carbon fiber bundles are placed, the graphite constituting 1% to 80% by mass, the method including a bundling step of bundling carbon fibers to form the carbon fiber bundles; a mixing step of mixing a refractory raw material with graphite to prepare a graphite-containing refractory raw material; a pressing step of pressing the graphite-containing refractory raw material in which the carbon fiber bundles are placed to prepare a formed product; and a drying step of drying the pressed product, wherein the bundling step includes bundling 1000 to 300000 of the carbon fibers with a fiber diameter of 1 to 45 μm/fiber to form carbon fiber bundles 100 mm or more in length.

A film is formed by use of a composition containing (A) a binder resin, (B) a hard particle, and (C) a solid lubricant selected from the group containing molybdenum disulfide and graphite, wherein the composition contains tungsten carbide as the hard particle, and wherein weight ratio of (B) the hard particles and (C) the solid lubricant, (B)/(C), is in the range of 1 to 3.