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. 05, 1999
Filed:
Aug. 29, 1997
Masamichi Yamagiwa, Itami, JP;
Akira Yamakawa, Itami, JP;
Takao Nishioka, Itami, JP;
Takashi Matsuura, Itami, JP;
Abstract
A silicon nitride ceramic sliding member which includes Si.sub.3 N.sub.4 grains as a main component and is shaped or controlled in dimensions through hot plastic working wherein the Si.sub.3 N.sub.4 particles mainly includes .beta.-type columnar crystal grains. The ceramic sliding member is produced by the step (I) of preparing a preform made of silicon nitride ceramic sintered body including Si.sub.3 N.sub.4 grains as a main component wherein the average grain size (average grain size in minor axis in the case of .beta.-type columnar crystal grains) of the Si.sub.3 N.sub.4 grains is at most 0.5 .mu.m, and the hot plastic working step (II) of placing the preform in a mold and effecting hot plastic deformation of the preform for shaping or dimensional control thereof while simultaneously increasing the average aspect ratio of the .beta.-type columnar crystal grains. The resultant sliding member has excellent sliding properties, a high mechanical strength and a high reliability at a low cost without resort to grinding or the like for shaping thereof.