Dresser Industries, Inc.

Ke-Chin Wang

Howard M Winkelbauer

Daniel R Petrak

Thomas R Kleeb

Eugene T Rushe

Kenneth W Hill

Frank H Walther, Jr

Donald F Stock

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.

Silicon nitride bonded magnesia refractory and method

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. The shapes may be tar impregnated to decrease coked porosity and to increase their resistance to mold powder.

Method of manufacturing an injection molded refractory shape and

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

Bonding a sialon coating to a substrate

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.

Refractory

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.

Nitride bonded oxide refractories

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

Fused silica shapes

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.

Preparation and composition of sialon grain and powder

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.

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Pittsburgh, PA, United States of America

Ke-Chin Wang