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:
Jan. 26, 1993
Filed:
Jun. 15, 1992
NGK Insulators, Ltd., , JP;
Abstract
A process for producing high density SiC sintered bodies by primarily firing and then hot isostatic pressing. The process includes the steps of formulating a powder consisting essentially of 90.0 to 99.8% by weight of the SiC powder, boron or a boron-containing compound in an amount of 0.1 to 5.0% by weight when calculated as boron, and carbon or a carbon-producing organic compound in an amount of 0.1 to 5.0% by weight when calculated as carbon, mixing and shaping the formulated powder, firing the shaped bodies in a temperature range from 1,900.degree. to 2,300.degree. C. in vacuum or in an inert gas atmosphere, and then hot isostatically pressing the fired bodies in a temperature range from 1,800.degree. to 2,200.degree. C. under a pressure of not less than 100 atms in an inert gas atmosphere. The SiC powder is an SiC mixed powder consisting essentially of 95.0 to 99.9% by weight of a first SiC powder composed of at least one kind of 3C and 2H polytypes and a second SiC powder composed of at least one kind of 6H, 4H and 15R polytypes and having an average grain diameter being less than twice that of the first SiC powder.