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. 15, 2019
Filed:
Aug. 31, 2015
Hitachi Metals, Ltd., Tokyo, JP;
Teppei Satoh, Mishima-gun, JP;
Futoshi Kuniyoshi, Mishima-gun, JP;
Rintaro Ishii, Mishima-gun, JP;
Ryouichi Yamagata, Mishima-gun, JP;
HITACHI METALS, LTD., Tokyo, JP;
Abstract
A method for manufacturing an R-T-B based sintered magnet includes: 1) a step of preparing an R-T-B based sintered magnet material by sintering a molded body, the sintered magnet material having a particular composition and satisfying inequality expressions (1) and (2); 2) a high-temperature heat treatment step of heating the sintered magnet material to a heating temperature of 730° C. to 1,020° C. and then cooling the sintered magnet material to 300° C. at a cooling rate of 5° C./min or more; and 3) a low-temperature heat treatment step of heating the sintered magnet material after the high-temperature heat treatment step to 440° C. to 550° C.:[T]−72.3[B]>0  (1)([T]−72.3[B])/55.85<13[Ga]/69.72  (2)where [T] is a T content in percent by mass, [B] is a B content in percent by mass, and [Ga] is a Ga content in percent by mass.