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:
Oct. 23, 2018
Filed:
Aug. 08, 2014
Applicant:
Tdk Corporation, Tokyo, JP;
Inventors:
Assignee:
TDK CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01F 1/057 (2006.01); H01F 1/055 (2006.01); C22C 38/00 (2006.01); C22C 38/06 (2006.01); C22C 38/10 (2006.01); C22C 38/16 (2006.01); H02K 1/02 (2006.01); H01F 41/02 (2006.01);
U.S. Cl.
CPC ...
H01F 1/0577 (2013.01); C22C 38/00 (2013.01); C22C 38/002 (2013.01); C22C 38/005 (2013.01); C22C 38/06 (2013.01); C22C 38/10 (2013.01); C22C 38/16 (2013.01); H01F 1/0551 (2013.01); H02K 1/02 (2013.01); B22F 2998/10 (2013.01); B22F 2999/00 (2013.01); C22C 2202/02 (2013.01); H01F 41/0293 (2013.01);
Abstract
The present invention provides an R-T-B based sintered magnet that inhibits the demagnetization rate at high temperature even when less or no heavy rare earth elements such as Dy, Tb and the like are used. The R-T-B based sintered magnet comprises RTB crystal grains and two-grain boundary parts between the RTB crystal grains. Two-grain boundary parts formed by a phase containing R, Cu, Co, Ga and Fe with a ratio of 40≤R≤70, 1≤Co≤10, 5≤Cu≤50, 1≤Ga≤15, and 1≤Fe≤40 (wherein, R+Cu+Co+Ga+Fe=100, and R is at least one selected from rare earth elements) exists in the magnet.