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:
Jul. 22, 1997
Filed:
Sep. 25, 1995
Yasunori Takahashi, Tokyo, JP;
Abstract
It is an object of the present invention to provide a method of producing sintered- or bond- rare earth element.iron.boron magnets obtainable easily and superior in magnetic properties with stable performance. The method of producing sintered rare earth element.iron.boron magnets according to the present invention is characterized by that it comprises steps of mixing in a scheduled ratio an acicular iron powder coated with a coating material, a rare earth element powder coated with a coating material and a boron powder coated with a coating material, and subjecting the mixture to compression molding followed by sintering of the molded mixture in the presence of a magnetic field. The method of producing bond rare earth element.iron.boron magnets according to the present invention is characterized by that it comprises steps of preparing a magnet powder by hydrogen-disintegration of the above-mentioned sintered magnet wherein a hydrogen-occluded sintered magnet resulted from heating the magnet under hydrogen atmosphere is subjected to hydrogen emission under substantial vacuum to cause disintegration of the hydrogen-occluded sintered magnet, coating the magnet powder with a coating material, mixing the coated magnet powder with a binder, and compression molding the mixture under heating in the presence of a magnetic field.