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:
Nov. 27, 2012
Filed:
Mar. 30, 2009
Futoshi Kuniyoshi, Osaka, JP;
Rintaro Ishii, Osaka, JP;
Futoshi Kuniyoshi, Osaka, JP;
Rintaro Ishii, Osaka, JP;
Hitachi Metals, Ltd., Tokyo, JP;
Abstract
An R-T-B based sintered magnet according to the present invention has a composition including: 27.3 mass % to 29.5 mass % of R; 0.92 mass % to 1 mass % of B; 0.05 mass % to 0.3 mass % of Cu; 0.02 mass % to 0.5 mass % of M; and T as the balance, and has an oxygen content of 0.02 mass % to 0.2 mass %. The main phase of the sintered magnet is an RTB type compound. The crystal grain size of the main phase is represented by an equivalent circle diameter of 8 μm or less. And crystal grains with equivalent circle diameters of 4 μm or less account for at least 80% of the overall area of the main phase.