Abstract: A refractory mix for forming a fused silica based refractory shape consisting essentially of a high purity fused silica and a binder system consisting essentially of a high purity colloidal silica solution and a high purity ammonium lignosulfonate. The invention also comprises fused silica based refractory shapes formed from such mix by pressing and firing.

Abstract: An oxidation-resistant carbon-containing refractory shape having on the surface thereof exposed to oxidation an oxidation-resistant glaze coating, said glaze coating consisting essentially of the reaction product of a zinc borosilicate frit and a clay; and the method of forming said coating on a refractory shape comprising applying to at least a portion of the shape an aqueous suspension of a fluxed mix consisting essentially of a zinc borosilicate and a clay, drying said coating, and firing said coated refractory shape at a temperature and for a time sufficient to cause the borosilicate and clay in said mix to react and form a substantially uniform glaze coating.

Abstract: A mix for forming a silicon nitride bonded magnesia refractory shape consisting essentially of; for each 100 wt. % thereof at least, about 3 to 20 wt. % of a high purity silicon powder containing no more than about 0.2 wt. % metallic impurities and, correspondingly, 97 to 80 wt. % of a high purity magnesite; and the resultant refractory shape formed after shaping of the mix and nitriding thereof and the method of making such shape.

Abstract: High purity silica powder formed from a sol-gel process is made from a quantity of an industrial grade hydrolizable silicon organometallic substance mixed with a quantity of an industrial grade organic solvent miscible in said organometallic substance and with a quantity of an acidified water having a pH less than 2 to form a solution. The solution is heated, then dried to form a gel, milled, and calcined to form the pure silica powder and the pure powder used to form encapsulated micro-miniature circuits.

Abstract: An alumina-carbon shape is manufactured from a composition comprising 1-8 weight percent fine silicon, 1-16 weight percent reactive alumina, 1-30 weight percent calcined fluidized bed coke, 1-30 weight percent of a spalling inhibiting additive, and the balance of the mix synthetic alumina, plus the additions of 5-10 weight percent of a high carbon yielding resin as a molding vehicle and 0.5-4 weight percent solvent, and up to 2 weight percent of a low temperature curing agent, such as, paraformaldehyde or hydrochloric acid. The mix is formed at ambient temperature into a shape through an injection molding process. Solidification is accomplished by curing in the mold at a temperature less than 100.degree. C. After stripping the shape from the mold, the solvents are removed from the shape by drying at a temperature above 100.degree. C. The shapes are then heated to a temperature above 550.degree. C. to coke the resin.

Abstract: A coating for a substrate includes a mix comprising sodium silicate, water and sialon powder. A defoaming agent is also added to the mix.

Abstract: A means for producing nitride bonded refractory shapes, in situ, by mixing an aluminum metal powder, relatively pure silica and a refractory aggregate. The mixes are pressed into shapes and burned at elevated temperatures in a nitriding atmosphere to form the bond.

Abstract: This invention relates to a method for producing nitride bonded refractory shapes in which the bonding matrix is formed in situ. The method comprises forming a batch including a coarser portion selected from the group calcined and fused aggregates of alumina, aluminosilicate, and magnesium aluminate spinel and a finer portion consisting essentially of finely divided silicon metal and alumina as well as fines of the above mentioned refractory aggregate needed to achieve the desired screen analysis. The silicon metal and alumina react in the nitriding atmosphere to form a low porosity matrix generally comprising silicon oxynitride with corundum distributed therethrough.

Abstract: Fused silica shapes having a coating of sialon on the surfaces thereof.

Abstract: Dense sialon grain is produced by briquetting mixtures of micronized silicon and reactive alumina. Sialon powder is produced by ball milling the briquettes after nitriding. The starting mixtures can contain from 10 to 38% reactive alumina with the balance of the mixture micronized silicon. Mixtures made within this range when pressed into dense briquettes and nitrided produce useful sialon grain having minimal free alumina contamination.

Abstract: A means for producing nitride bonded refractory shapes, in situ, by mixing an aluminum metal powder, relatively pure silica, crude clay and a refractory aggregate. The mixes are pressed into shapes and burned at elevated temperatures in a nitriding atmosphere to form the bond.