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:
Jul. 23, 1991
Filed:
Jul. 16, 1990
Ken Ohashi, Fukui, JP;
Yoshio Tawara, Fukui, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
The magnetic properties or, in particular, coercive force of a sintered permanent magnet composed of a light rare earth element, boron and iron can be greatly improved without affecting the residual magnetic flux by the admixture of a relatively small amount of additive elements including heavy rare earth elements, aluminum, titanium, vanadium, niobium and molybdenum. In the inventive magnets, the distribution of the additive element is not uniform but localized in the vicinity of the grain boundaries of the matrix particles. Such a localized distribution of the additive elements is obtain by sintering a powder mixture composed of a powder of an alloy of the base ingredients and a powder containing the additive element or elements.