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. 19, 1999
Filed:
Mar. 27, 1998
Shinya Sakurada, Tokyo, JP;
Tomohisa Arai, Yokohama, JP;
Keisuke Hashimoto, Yokohama, JP;
Takahiro Hirai, Kamakura, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A permanent magnet material has a principal phase of TbCu7 type crystal structure and improved magnetic properties. This permanent magnet material is represented by the general formula: R1.sub.x R2.sub.y B.sub.z N.sub.u M.sub.100-x-y-z-u, wherein R1 is at least one rare earth element including Y, R2 is at least one element selected from the group consisting of Zr, Hf and Sc, M is at least one element selected from Fe and Co, x, y, z and u are atomic percents individually defined as x.gtoreq.2, y.gtoreq.0.01, 4.ltoreq.x+y.ltoreq.20, 0.ltoreq.z.ltoreq.10, and 0<u.ltoreq.20. The permanent magnet material has a principal phase of a TbCu.sub.7 type crystal structure. The permanent magnet material satisfies the relation of t.ltoreq.60 and .sigma./t.ltoreq.0.7, wherein t(nm) is an average crystal grain size of the principal phase and .sigma.(nm) is a standard deviation of the crystal grain size.