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:
Dec. 05, 2000
Filed:
Oct. 06, 1995
Motoyuki Nishizawa, Kawasaki, JP;
Mineharu Tsukada, Kawasaki, JP;
Kaoru Hashimoto, Kawasaki, JP;
Nobuo Kamehara, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
In a method of manufacturing piezoelectric ceramics by molding pre-fired or calcined powders of ingredients of a piezoelectric ceramic material and sintering the powder mold at a high pressure, the powder mold is pre-sintered at an atmospheric pressure before sintering at high pressure (HIP). Preferably, after the sintering HIP step, a thermal treatment is performed at a temperature of from 500 to 1000.degree. C. under an oxidizing atmosphere. For a Pb(Zn.sub.1/3 Nb.sub.2/3)O.sub.3 --PbTiO.sub.3 based piezoelectric ceramic, the composition is preferably set to (Pb.sub.1-x Ba.sub.x)[(Zn.sub.1/3 Nb.sub.2/3).sub.1-y Ti.sub.y ]O.sub.3, where 0.001<x<0.055 and 0.05<y<0.20.