Gte Products Corporation

Robert F Northrop

Geoffrey L Harris

David R Moyle

A method is disclosed for producing tungsten carbide and a cemented tungsten carbide article therefrom which consists essentially of forming a uniform mixture of tungsten metal powder and carbon wherein the tungsten metal powder has an aveage particle size of from about 1 to about 4 micrometers in diameter, wherein the surface area of the carbon is no greater than about 12 m.sup.2 /g, and wherein the amount of the carbon is sufficient to react with essentially all of the tungsten to produce tungsten carbide in the subsequent heating step, heating the mixture in a non-oxidizing atmosphere at a temperature of at least about 1200.degree. C. for a sufficient time to produce tungsten carbide wherein the amount of free carbon is less than about 0.05% by weight and wherein the tungsten carbide has an average particle size of from about 1 to about 4 micrometers in diameter, forming a uniform second mixture of the tungsten carbide powder, a wax binder, and cobalt powder wherein the cobalt content of the second mixture is from about 3% to about 20% by weight of the second mixture, forming a green article from the second mixture, and sintering the green article at a temperature of from about 1400.degree. C. to about 1300.degree. C. to produce the cemented tungsten carbide article wherein the microstructure of the cemented tungsten carbide article exhibits an average of no more than 1 grain having a particle size of greater than about 7 micrometers in diameter per about 0.15 cm.sup.2 of surface of the article.

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Towanda, PA, United States of America

Robert F Northrop