A CVD-SiC formed body has low light transmittance and high resistivity, and may suitably be used as a member for an etcher that is used for a semiconductor production process, for example. The SiC formed body is formed using a CVD method, and includes 1 to 30 mass ppm of boron atoms, and more than 100 mass ppm and 1000 mass ppm or less of nitrogen atoms. The SiC formed body preferably has a resistivity of more than 10 .Math.cm and 100,000 .Math.cm or less, and a light transmittance at a wavelength of 950 nm of 0 to 1%.

A composition having nanoparticles of a boron carbide and a carbonaceous matrix. The composition is not in the form of a powder. A composition comprising boron and an organic component. The organic component is an organic compound having a char yield of at least 60% by weight or a thermoset made from the organic compound. A method of combining boron and an organic compound having a char yield of at least 60% by weight, and heating to form boron carbide or boron nitride nanoparticles.

A polycrystalline composite comprising diamond particles and non-diamond carbon, wherein: the sum of the content Vd of the diamond particles and the content Vg of the non-diamond carbon is more than 99% by volume based on the total volume of the polycrystalline composite; the median diameter d50 of the diamond particles is 10 nm or more and 200 nm or less; the dislocation density of the diamond particles is 1.010.sup.13 m.sup.2 or more and 1.010.sup.16 m.sup.2 or less; and the content Vd of the diamond particles and the content Vg of the non-diamond carbon satisfy the relationship represented by the formula 1:0.01<Vg/(Vd+Vg)0.5 Formula 1.

Methods for fabricating a ceramic matrix composite are disclosed. A fiber preform may be placed in a mold. An aqueous solution may be added to the fiber preform. The aqueous solution may include water, carbon nanotubes, and a binder. The preform may be frozen. Freezing the preform may cause the water to expand and separate fibers in the fiber preform. The carbon nanotubes may bond to the fibers. The preform may be freeze dried to remove the water. The preform may then be processed according to standard CMC process.

A method of producing, from a continuous or discontinuous (e.g., chopped) carbon fiber, partially to fully converted metal carbide fibers. The method comprises reacting a carbon fiber material with at least one of a metal or metal oxide source material at a temperature greater than a melting temperature of the metal or metal oxide source material (e.g., where practical, at a temperature greater than the vaporization temperature of the metal or metal oxide source material). Additional methods, various forms of carbon fiber, metal carbide fibers, and articles including the metal carbide fibers are also disclosed.

A multi-component or composite inorganic fiber comprising a nano-scale contiguous collection of a plurality of packed unique phases of material randomly interspersed throughout the fiber body, without unwanted impurities, and a method for producing same. Said phases include three or more foundational chemical elements from the Periodic Table mixed together during fiber production, producing distinct material phases interspersed throughout the fiber volume.

A method of fabricating a part made of ceramic matrix composite material, the method includes fabricating the part by forming a ceramic matrix in the pores of a fiber structure, the ceramic matrix being formed by self propagating high temperature synthesis from a powder composition present in the pores of the fiber structure,

A component includes a component body in which at least one cavity is formed, wherein a wall surface of the component body, which wall surface delimits the cavity, is at least partially coated with a coating. The design of the component is based on a porous preform made in one or more parts from an inorganic matrix (M1), the preform having the cavity and a porous pre-coating made from an inorganic matrix (M2), the pre-coating coating at least part of a wall surface of the preform that delimits the cavity The porous preform and the porous pre-coating are infiltrated with an inorganic infiltrate (M3). The infiltrated preform forms the component body, and the infiltrated pre-coating forms the coating. A method for producing the component, wherein the preform and the pre-coating are infiltrated so as to produce the component body comprising the coating is also disclosed.

The present invention relates to a porous alpha-SiC-containing shaped body with a gas-permeable, open-pored pore structure comprising platelet-shaped crystallites which are connected to form an interconnected, continuous skeletal structure, wherein the skeletal structure consists of more than 80 wt.-% alpha-SiC, relative to the total weight of SiC, a process for producing same and its use as a filter component.

A ceramic article includes a ceramic matrix composite that has a porous reinforcement structure and a ceramic matrix within pores of the porous reinforcement structure. The ceramic matrix composite includes a surface zone and a glaze material within pores of the surface zone and on an exterior side of the surface zone as an exterior glaze layer.