Systems and methods for making ceramic powders configured with consistent, tailored characteristics and/or properties are provided herein. In some embodiments a system for making ceramic powders, includes: a reactor body having a reaction chamber and configured with a heat source to provide a hot zone along the reaction chamber; a sweep gas inlet configured to direct a sweep gas into the reaction chamber and a sweep gas outlet configured to direct an exhaust gas from the reaction chamber; a plurality of containers, within the reactor body, configured to retain at least one preform, wherein each container is configured to permit the sweep gas to flow therethrough, wherein the preform is configured to permit the sweep gas to flow there through, such that the precursor mixture is reacted in the hot zone to form a ceramic powder product having uniform properties.

A thermoelectric conversion material made of a sintered body containing a magnesium silicide as a major component includes: a magnesium silicide phase; and a magnesium oxide layer formed on a surface layer of the magnesium silicide phase, in which an aluminum concentrated layer having an Al concentration higher than an aluminum concentration in an inside of the magnesium silicide phase is formed between the magnesium oxide layer and the magnesium silicide phase, and the aluminum concentrated layer has a metallic aluminum phase including aluminum or an aluminum alloy.

A composite sintered body, wherein the composite sintered body consists of ceramic composite sintered body, the ceramic composite sintered body comprises aluminum oxide as a main phase, and silicon carbide as a sub-phase, in which the composite sintered body has mullite in crystal grains of the aluminum oxide.

A ceramic and a method of forming a ceramic including milling steel slag exhibiting a diameter of 5 mm of less to form powder, sieving the powder to retain the powder having a particle size in the range of 20 to 400 removing free iron from the powder with a magnet, heat treating the powder at a temperature in the range of 700° C. to 1200° C. for a time period in the range of 1 hour to 10 hours and oxidizing retained iron in the powder, compacting the powder at a compression pressure in the range of 20 MPa to 300 MPA, and sintering the powder at a temperature in the range of 700° C. to 1400° C. for a time period in the range of 0.5 hours to 4 hours to provide a ceramic.

A method of manufacturing a coated reinforcing fiber for use in Ceramic Matrix Composites, the method comprising pre-oxidizing a plurality of silicon-based fibers selected from the group consisting of silicon carbide (SiC) fibers, silicon nitride (Si.sub.3N.sub.4) fibers, SiCO fibers, SiCN fibers, SiCNO fibers, and SiBCN fibers at between 700 to 1300 degrees Celsius in an oxidizing atmosphere to form a silica surface layer on the plurality of silicon-based fibers, forming a plurality of pre-oxidized fibers; applying a rare earth orthophosphate (REPO.sub.4) coating to the plurality of pre-oxidized fibers; and heating the plurality of REPO.sub.4 coated pre-oxidized fibers at about 1000-1500 degrees Celsius in an inert atmosphere to react the REPO.sub.4 with the silica surface layer to form a rare earth silicate or disilicate. The pre-oxidizing step may be 0.5 hours to about 100 hours. The heating step may be about 5 minutes to about 100 hours.

A method of manufacturing a coated reinforcing fiber for use in Ceramic Matrix Composites, the method comprising pre-oxidizing a plurality of silicon-based fibers selected from the group consisting of silicon carbide (SiC) fibers, silicon nitride (Si.sub.3N.sub.4) fibers, SiCO fibers, SiCN fibers, SiCNO fibers, and SiBCN fibers at between 700 to 1300 degrees Celsius in an oxidizing atmosphere to form a silica surface layer on the plurality of silicon-based fibers, forming a plurality of pre-oxidized fibers; applying a rare earth orthophosphate (REPO.sub.4) coating to the plurality of pre-oxidized fibers; and heating the plurality of REPO.sub.4 coated pre-oxidized fibers at about 1000-1500 degrees Celsius in an inert atmosphere to react the REPO.sub.4 with the silica surface layer to form a rare earth silicate or disilicate. The pre-oxidizing step may be 0.5 hours to about 100 hours. The heating step may be about 5 minutes to about 100 hours.

This innovation provides for a revolutionary advancement in the area of very thick and very high thermal conductivity carbon-carbon (C—C) composites for both commercial and military. Novel, surface treated to achieve desired chemistry, exhibiting no agglomeration, carbon-based fillers are used enabling stable slurries up to 45 wt % solids to be used in the composite pre-pregging for 1-D and 2-D, 2-5 D and 3-D preforms infiltration. The need for carbonization is eliminated. No closed porosity C—C composites are produced. Up to 12″ thick C—C composites with no density gradient and thermal conductivity in excess of 650 W/mK were fabricated via chemically induced graphitization.

The present invention provides a dental product comprising a base material formed of a zirconia sintered body, and having high aesthetic quality with enhanced fracture toughness and with reduced chipping and cracking in the porcelain layer. The present invention also provides a method for manufacturing such a dental product. The present invention relates to a dental product comprising: a base material formed of a zirconia sintered body, and a porcelain layer, wherein the porcelain of the porcelain layer has a suitable firing temperature of 900° C. or more, and the porcelain layer has a fracture toughness value of 1.20 MPa.Math.m.sup.0.5 or more.

The present invention is within in the field of ceramic material for biomedical applications. The present invention relates to a silicon oxynitride powder or an oxidized silicon nitride powder having the general chemical formula Si.sub.xO.sub.yN.sub.z. The powder comprises 0.1-50 wt % oxygen, or 7-12 wt % oxygen, or 10-12 wt % oxygen. The silicon oxynitride powder according to the invention is suitable for anti-pathogen applications.

A sintered composite ceramic, including: a lithium-garnet major phase; and a grain growth inhibitor minor phase, such that the grain growth inhibitor minor phase has a metal oxide in a range of 0.1 wt. % to 10 wt. % based on the total weight of the sintered composite ceramic.