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:
Oct. 27, 1998
Filed:
Sep. 29, 1995
Masashi Yoshimura, Itami, JP;
Takeshi Satoh, Itami, JP;
Akira Yamaguchi, Itami, JP;
Akira Yamakawa, Itami, JP;
Abstract
A process for the production of a silicon nitride sintered body which comprises heat-treating a stock of silicon nitride sintered body within a temperature range of from the temperature at which the internal friction of the stock exhibits a peculiar peak maximum minus 150.degree. C. to that plus 150.degree. C. A representative used in the process is one which is produced by mixing powdered silicon nitride with powdery sintering aids so as to give a powder mixture comprising 5 to 15% by weight (in terms of oxide) of at least one element selected from the group consisting of rare earth elements and aluminum, 0.5 to 5% by weight (in terms of oxide) of at least one element selected from the group consisting of Mg, Ti and Ca and the balance of Si.sub.3 N.sub.4, molding the powder mixture, and sintering the resulting compact in a nitrogen-containing atmosphere at 1500.degree. to 1700.degree. C.