A method of forming a magnetically anisotropic powder includesthe steps of forming a substantially spherical powder having amajor magnetic phase and an average particle size of less thanabout 200 microns, diffusing hydrogen into the spherical powder atelevated temperatures in an amount sufficient to disproportionatethe major magnetic phase, and desorbing the hydrogen by heating thedisproportionated powder under vacuum. The magnetic material fromwhich the spherical powder is formed may be a rare earth-transitionmetal-boron alloy including at least one element from the irongroup, at least one rare earth element, and boron. A method offorming a bonded magnet containing magnetically anisotropicparticles further includes the steps of mixing the dehydrogenatedpowder with a binder to form a mixture, and aligning and magnetiz-ing the powder particles in the mixture in a magnetic field. Bonded magnets containing spherical, magnetically anisotropicparticles of the invention have intrinsic coercivities in excess of7kOe.

Poudre spherique magnetiquement anisotrope
Magnetically anisotropic spherical powder
Publication Number
Application Date
May 26, 1994
Publication Date
October 17, 2006
Liang Yu Lan Wang
Liu Wan Li
Ma Bao Min
Santoku Corporation
Rhone Poulenc Specialty Chemicals Co
H01F 41/02
H01F 01/22
H01F 01/20
H01F 01/057
H01F 01/053
H01F 01/06
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