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. 09, 2019
Filed:
Feb. 16, 2016
Tdk Corporation, Tokyo, JP;
Akihiro Ohsawa, Tokyo, JP;
Yasushi Enokido, Tokyo, JP;
TDK CORPORATION, Tokyo, JP;
Abstract
A rare earth based permanent magnet formed by a sintered compact with an R-T-B based composition, wherein, R contains R1 and R2 as the necessity, R1 represents at least one rare earth element including Y and excluding Dy, Tb and Ho, and R2 represents at least one from the group made of Dy, Tb and Ho. Its main phase grains have a core-shell structure in which a core part and shell part coating the core part are contained. When the atom concentrations of R1 and R2 in the core part and the atom concentrations of R1 and R2 in the shell part are defined as αR1, αR2, βR1 and βR2, respectively, αR1<βR1, αR2>βR2, αR1<αR2 and βR2<βR1. Relative to all the main phase grains observed at the cross-section of the sintered compact, the ratio occupied by the main phase grain having the core-shell structure is 5% or more.