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:
Aug. 18, 2020
Filed:
Mar. 29, 2018
Tdk Corporation, Tokyo, JP;
Yoshinori Fujikawa, Tokyo, JP;
Masashi Miwa, Tokyo, JP;
TDK CORPORATION, Tokyo, JP;
Abstract
An R-T-B based sintered magnet including a plural number of main phase particles having an RTB type crystal structure. R is at least one rare earth element essentially including heavy rare earth elements RH, T is at least one transition metal element essentially including Fe or Fe and Co, and B is boron. At least one of the main phase particles is a reverse core-shell main phase particle including a core part and a shell part, in which C/C>1.0 is satisfied when a total RH concentration (at %) in the core part is defined as Cand a total RH concentration (at %) in the shell part is defined as C. An existence ratio of the reverse core-shell main phase particles is larger in a surface layer part of the magnet than in a central part of the magnet.