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. 23, 2013
Filed:
Jul. 08, 2011
Takuma Hayakawa, Tokyo, JP;
Ryouta Kunieda, Tokyo, JP;
Takuma Hayakawa, Tokyo, JP;
Ryouta Kunieda, Tokyo, JP;
TDK Corporation, Tokyo, JP;
Abstract
A rare earth sintered magnet includes a main phase that includes an RTB phase of crystal grain where R is one or more rare earth elements including Nd, T is one or more transition metal elements including Fe or Fe and Co, and B is B or B and C; a grain boundary phase in which a content of R is larger than a content of the RTB phase; and a grain boundary triple point that is surrounded by three or more main phases. The grain boundary triple point includes an R75 phase containing R of 60 at % to 90 at %, Co, and Cu. The relational expression 0.05≦(Co+Cu)/R<0.5 is satisfied. An area where a Co-rich region overlaps with a Cu-rich region in a cross-sectional area of the grain boundary triple point is 60% or more.