A process for producing a process for producing a LnM.sub.2Cu.sub.3O.sub.x high-temperature superconductive powder, the process comprising: i) providing an aqueous solution of Ln, M and Cu and at least one mineral acid; ii) adding at least one sequestrating agent and, optionally, at least one dispersant to the solution to form a precipitate; iii) recovering the precipitate from the solution; and iv) heating the precipitate in a flow of oxygen to form the LnM.sub.2Cu.sub.3O.sub.x powder, wherein Ln is a rare earth element, preferably Y, Ce, Dy, Er, Gd, La, Nd, Pr, Sm, Sc, Yb, or a mixture of two or more thereof, and wherein M is selected from Ca, Sr, and Ba.

A composite sintered material includes a plurality of diamond grains, a plurality of cubic boron nitride grains, and a remainder of a binder phase, wherein the binder phase includes cobalt, a content of the cubic boron nitride grains in the composite sintered material is more than or equal to 3 volume % and less than or equal to 40 volume %, and an average length of line segments extending across continuous cubic boron nitride grains in appropriately specified straight lines extending through the composite sintered material is less than or equal to a length three times as large as an average grain size of the cubic boron nitride grains.

A thermoelectric conversion material formed of a sintered body containing magnesium silicide as a main component contains 0.5 mass % or more and 10 mass % or less of aluminum oxide. The aluminum oxide is distributed at a crystal grain boundary of the magnesium silicide.

The present invention relates to a granular thermal insulation material comprising hydrophobized silicon dioxide and at least one IR opacifier, having a tamped density of up to 250 g/l and a compressive strength according to DIN EN 826:2013 at 50% compression of 150 to 300 kPa or greater than 300 kPa, to processes for production thereof and to the use thereof for thermal insulation.

Provided is a method for producing a -sialon fluorescent material, comprising preparing a composition containing a silicon nitride that contains aluminium, oxygen, and europium; heat-treating the composition at a temperature in a range of 1300 C. or more and 1600 C. or less to obtain a heat-treated product; subjecting the heat-treated product to a temperature-decrease of from the heat treatment temperature to 1000 C. as a first temperature-decrease step; and subjecting the heat-treated product to a temperature-decrease of from 1000 C. to 400 C. as a second temperature-decrease step. The first temperature-decrease step has a temperature-decrease rate in a range of 1.5 C./min or more and 200 C./min or less, and the second temperature-decrease step has a temperature-decrease rate in a range of 1 C./min or more and 200 C./min or less

Aluminum nitride crystal particles, aluminum nitride powders containing the same, production processes for both of them, an organic polymer composition comprising the aluminum nitride crystal particles and a sintered body. Each of the aluminum nitride crystal particles has a flat octahedral shape in a direction where hexagonal faces are opposed to each other, which is composed of two opposed hexagonal faces and 6 rectangular faces, in which the average distance D between two opposed corners of each of the hexagonal faces is 3 to 110 m, the length L of the short side of each of the rectangular faces is 2 to 45 m, and L/D is 0.05 to 0.8; each of the hexagonal faces and each of the rectangular faces cross each other to form a curve without forming a single ridge; and the true destiny is 3.20 to 3.26 g/cm.sup.3.

To provide a sintered material having excellent oxidation resistance, as well as excellent abrasion resistance and chipping resistance. A sintered material containing a first compound formed of Ti, Al, Si, O, and N is provided.

A method of producing ceramic wafer includes a forming step and processing step. The processing step includes forming positioning notch or positioning, flat edge and edge profile, which avoids the ceramic wafers to have processing defect during cutting, grinding, and polishing, for increasing yield. The ceramic particles for producing ceramic wafer include nitride ceramic powder, oxide ceramic powder, and nitride ceramic powder. The ceramic wafer has low dielectric constant, insulation, and excellent heat dissipation, which can be applied for the need of semiconductor process, producing electric product and semiconductor equipment.

A method for forming a ceramic matrix composite bearing includes preparing a layup slurry from a mixture of water, pre-ceramic polymer and refractory filler. The method further includes forming a concentric stack of slurry-impregnated fabric sleeve layers over a rod-shaped inner mold and applying an outer mold to form a mold assembly. The method also includes heating the mold assembly to form a tubular green body and rough cutting the green body to bearing length. In addition, the method includes heat-treating the bearing and performing a polymer infiltration and pyrolysis treatment. The method further includes conducting dimensional stability treatment processes on the bearing and final grinding and machining to meet pre-determined specifications.

A carbon plate including the following components in weight percentage: 31.5% to 91% of carbon powder, 3% to 25% of resin, 3% to 30% of plant fiber, 0.5% to 2.5% of fire retardant, 0.5% to 3% of dispersing agent, 1% to 3% of zeolite powder, and 1% to 5% of tea stem residue. A manufacturing process for the carbon plate including: mixing raw materials according to a proportion, placing the raw materials into a stirrer, and stirring the raw materials to uniformity; feeding a material obtained; performing heating; maintaining the pressure.