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:
Feb. 21, 1989
Filed:
Apr. 30, 1987
Applicant:
Inventors:
Tsuneyuki Kanai, Hitachi, JP;
Tadahiko Miyoshi, Hitachi, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C04B / ;
U.S. Cl.
CPC ...
501 97 ; 501 98 ;
Abstract
There is obtained, by mixing oxide raw material powders, compacting the mixture and sintering the compact, a silicon nitride sintered body mainly composed of silicon nitride and having a grain boundary phase wherein crystals represented by Yb.sub.2 Si.sub.2 O.sub.7 and a Zr.sub.3 Yb.sub.4 O.sub.12 are present in the grain boundary phase and molar ratio ZrO.sub.2 /Yb.sub.2 O.sub.3 in terms of ZrO.sub.2 and Yb.sub.2 O.sub.3 is 2/98 to 75/25 and the total amount of ZrO.sub.2 and Yb.sub.2 O.sub.3 is 1-40% by weight of the sintered body.