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:
Apr. 18, 2017
Filed:
Apr. 22, 2014
Tdk Corporation, Tokyo, JP;
Yasushi Enokido, Tokyo, JP;
Daisuke Tanaka, Tokyo, JP;
TDK CORPORATION, Tokyo, JP;
Abstract
The present invention provides a permanent magnet with a coercivity that will not be significantly decreased and a light weight compared to conventional R-T-B based permanent magnets. A core-shell structure is formed for the major phase grain by adding Cu to the R-T-B based magnet which is the raw material. When the mass concentration of Y in the core portion is set as EY, the mass concentration of Y in the shell portion is set as LY and the mass concentration of Y in the R—Fe—B crystal grain calculated from the ratio R1:Y in the total composition is set as SY, the ratio α of EY to SY (EY/SY) is 1.1 or more. Thus, the magnetic insulation among the crystal grains becomes better which prevents the coercivity from decreasing due to the addition of Y. Further, the addition of Y makes the magnet lighter in weight.