Title:
PRODUCTION OF RARE-EARTH MAGNETIC ALLOY POWDER AND ANISOTROPIC BONDED MAGNET
Document Type and Number:
Japanese Patent JP3410171
Kind Code:
B2
Abstract:
PURPOSE: To produce a rare-earth magnetic alloy powder having excellent magnetic characteristics such as coercive force, magnetization quantity and superior quality by performing the dehydrogenation process at a specified rate in the hydrogen occlusion and dehydrogenation processes of the alloy powder consisting of rare-earth elements, transition metals and boron.
CONSTITUTION: This rare-earth magnetic alloy powder consisting of the aggregate of fine crystal grains having 0.02 to 5μm average crystal grain size and consisting essentially of R2T14B (wherein R is rare-earth element containing Y and T is a transition metal) is subjected to hydrogen occlusion and dehydrogenation processing to effect recrystallization reaction. The composition of the rare-earth magnetic alloy consists of 25 to 35wt.% R, 0.5 to 1.5wt.% B, 3 to 20wt.% Co, 0.05 to 5wt.% of at least one metal selected among Ga, Zr, Hf, Nb, Ta, etc., and the balance Fe. Further, the dehydrogenation process is performed under the degree of vacuum (Y) expressed by an exponential function Y=A×Z (wherein Z is -0.7 to -0.3) in the range of 60 to 1000sec dehydrogenation time (X).
Inventors:
Katsunori Iwasaki
Minoru Endo
Masaaki Tokunaga
Minoru Endo
Masaaki Tokunaga
Application Number:
JP24125193A
Publication Date:
May 26, 2003
Filing Date:
September 28, 1993
Export Citation:
Assignee:
Hitachi Metals Co., Ltd.
International Classes:
C22C38/00; H01F1/053; H01F1/057; H01F1/06; H01F1/08; H01F7/02; B22F1/00; (IPC1-7): B22F1/00; H01F1/053; H01F1/06; H01F1/08; H01F7/02