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:
Sep. 17, 1991
Filed:
Sep. 07, 1989
Applicant:
Inventors:
Assignee:
NGK Spark Plug Co., Ltd., Aichi, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C04B / ;
U.S. Cl.
CPC ...
501 98 ; 501 97 ;
Abstract
A sintered body of silicon nitride having high strength, toughness and oxidation resistance consists essentially of, by weight percentages, 0.5 to 7.0% of a Mg component calculated as MgO, 0.5 to 7.0% of a Zr component calculated as ZrO.sub.2, 0.5 to 10.0% of a Ce component calculated as CeO.sub.2, and the balance being Si.sub.3 N.sub.4. The sum of Mg, Zr and Ce components calculated as oxides is 3 to 20% by weight. This product is suitable for engine parts or cutting tools.