The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 23, 1999
Filed:
Oct. 02, 1996
Purnesh Seegopaul, Flemington, NJ (US);
Nanodyne Incorporated, New Brunswick, NJ (US);
Abstract
Grain growth inhibitors including vanadium carbide, chromium carbide, tantalum carbide, and niobium carbide are incorporated into a cobalt/tungsten carbide matrix during the formation of the cobalt/tungsten carbide matrix. A precursor powder is formed by combining in solution a cobalt composition, a tungsten composition and a grain growth inhibiting metal composition, which is then spray dried. The precursor compound is then carburized in carbon monoxide and carbon dioxide to form cobalt/tungsten carbide matrix. This is then further carburized in a hydrocarbon hydrogen gas at an elevated temperature to cause the grain growth inhibiting metal present to form the carbide. The second carburizing step is conducted with a carburizing gas having a carbon activity greater than about 2 for a relatively short period of time at 900.degree. C. to 1000.degree. C.