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:
Mar. 05, 2002
Filed:
Jul. 14, 2000
Oliver Gutfleisch, Dresden, DE;
Michael Kubis, Dresden, DE;
Axel Handstein, Dresden, DE;
Bernhard Gebel, Coswig, DE;
Karl-Hartmut Mueller, Dresden, DE;
Ivor Harris, Birmingham, GB;
Ludwig Schultz, Pappritz, DE;
Abstract
A method is disclosed enabling a technologically controllable and economical production of a hard-magnetic powder composed of a samarium-cobalt base alloy for highly coercive permanent magnets. The method is based on a HDDR treatment in which a starting powder is subjected to hydrogenation with disproportionation of the alloy in a first method step under hydrogen and, in a subsequent, second method step under vacuum conditions, a hydrogen desorption with recombination of the alloy. A starting powder containing samarium and cobalt is treated in the first method step either at a high temperature in the range of 500° C. to 900° C. and with a high hydrogen pressure of >0.5 MPa or by applying an intensive fine grinding at a low temperature in the range of 50° C. to 500° C. and with a hydrogen pressure of >0.15 MPa. By means of the method of the invention, magnetic alloy powders can be produced from samarium-cobalt base alloys; highly coercive permanent magnets can be produced from these magnetic alloy powders, particularly by hot compacting or plastic bonding.