A process for preparing roofing granules includes forming kaolin clay into green granules and sintering the green granules at a temperature of at least 900 degrees Celsius to cure the green granules until the crystalline content of the sintered granules is at least ten percent as determined by x-ray diffraction.

Polysilocarb formulations, cured and pyrolized materials, was well as articles and use for this material. In particular pyrolized polysilocarb ceramic materials and articles contain these materials where, the ceramic has from about 30 weight % to about 60 weight % silicon, from about 5 weight % to about 40 weight % oxygen, and from about 3 weight % to about 35 weight % carbon, and wherein 20 weight % to 80 weight % of the carbon is silicon-bound-carbon and 80 weight % to about 20 weight % of the carbon is free carbon.

Nanocomposite silicon and carbon compositions. These compositions can be made from polymer derived ceramics, and in particular, polysilocarb precursors. The nanocomposite can have non-voids or be nano-void free and can form larger macro-structures and macro-composite structures. The nanocomposite can contain free carbon domains in an amorphous SiOC matrix.

A molding tool made of carbon or graphite, namely a casting mold or a casting core for the processing of molten metal or to a molding tool for the processing of molten glass, such as for example a blow mold and a method for producing the molding tool.

A porous refractory cast material contains a closed refractory aggregate fraction having a minimum particle size and a maximum particle size; the ratio of maximum particle size to minimum particle size is 10:1 or less. This closed refractory aggregate fraction comprises all of the porous refractory cast material having a particle diameter greater than 0.1 mm. The porous refractory cast material also contains a binder phase containing refractory selected from calcium aluminate cement, alumina phosphate, hydratable alumina, colloidal silica and combinations thereof. Also disclosed is a metallurgical vessel with an interior lining incorporating the porous refractory cast material.

The invention relates to a process for producing proppants, including the following steps: providing red mud, providing fly ash, producing a mixture from the red mud and the fly ash so that the mixture has a first moisture content in the range of 7 to 30 wt. %, producing a granular product from the mixture, and sintering the granular product.

The present invention is directed to a method for producing a silicon nitride sintered material, the method including heating a molded article, which contains a silicon nitride powder having a β phase ratio of 80% or more, a dissolved oxygen content of 0.2% by mass or less, and a specific surface area of 5 to 20 m.sup.2/g, and a sintering auxiliary containing a compound having no oxygen bond, and which has an overall oxygen content controlled to be 1 to 15% by mass and an aluminum element overall content controlled to be 800 ppm or less, to a temperature of 1,200 to 1,800° C. in an inert gas atmosphere under a pressure of 0 MPa.Math.G or more and less than 0.1 MPa.Math.G to sinter the silicon nitride.

In the present invention, there can be provided a method for producing a silicon nitride sintered material, which method is advantageous in that a silicon nitride sintered material having high thermal conductivity can be obtained even when using a silicon nitride powder having a high β phase ratio and conducting calcination under normal pressure or substantially normal pressure.

A dry backfill for producing a basic molded heavy-clay refractory product, to such a product and a method for producing the same, to a lining of an industrial furnace, and to an industrial furnace.

Provided is a ZrO.sub.2—CaO—C based refractory material which is capable of maintaining high adhesion resistance over a long period of time, while exhibiting significant slaking resistance, and suppressing self-fluxing, i.e., exhibiting corrosion-erosion resistance. The refractory material comprises a CaO—ZrO.sub.2 composition containing a CaO component in an amount of 40% by mass to 60% by mass, wherein a mass ratio of the CaO component to a ZrO.sub.2 component is 0.67 to 1.5, and wherein the CaO—ZrO.sub.2 composition includes a eutectic microstructure of CaO crystals and CaZrO.sub.3 crystals, wherein a width of each of the CaO crystals observable in a cross-sectional microstructure is 50 μm or less.

A ceramic component, wherein the component contains 20 to 60 wt. % SiC, 5 to 40 wt. % free silicon and 10 to 65 wt. % free carbon. The disclosure also relates to the use of the component. The method for producing the ceramic component includes the following steps: a) providing a green body based on carbon, which has been produced by means of a 3D-printing method, b) impregnating the green body with a solution selected from the group consisting of a sugar solution, a starch solution or a cellulose solution, or a resin system including a mixture containing at least one resin, at least one solvent and at least one curing agent, wherein the at least one resin and the at least one solvent are different, c) drying or curing the impregnated green body.