Metal treatment – Stock – Magnetic
Patent
1995-11-29
1998-09-08
Sheehan, John
Metal treatment
Stock
Magnetic
420 83, 420121, 148121, H01F 1057
Patent
active
058039929
ABSTRACT:
A method of making a permanent magnet wherein 1) a melt is formed having a base alloy composition comprising RE, Fe and/or Co, and B (where RE is one or more rare earth elements) and 2) TR (where TR is a transition metal selected from at least one of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and Al) and at least one of C and N are provided in the base alloy composition melt in substantially stoichiometric amounts to form a thermodynamically stable compound (e.g. TR carbide, nitride or carbonitride). The melt is rapidly solidified in a manner to form particulates having a substantially amorphous (metallic glass) structure and a dispersion of primary TRC, TRN and/or TRC/N precipitates. The amorphous particulates are heated above the crystallization temperature of the base alloy composition to nucleate and grow a hard magnetic phase to an optimum grain size and to form secondary TRC, TRN and/or TRC/N precipitates dispersed at grain boundaries. The crystallized particulates are consolidated at an elevated temperature to form a shape. During elevated temperature consolidation, the primary and secondary precipitates act to pin the grain boundaries and minimize deleterious grain growth that is harmful to magnetic properties.
REFERENCES:
patent: 4597938 (1986-07-01), Matsuura et al.
patent: 4601875 (1986-07-01), Yamamoto et al.
patent: 4801340 (1989-01-01), Inoue et al.
patent: 4919732 (1990-04-01), Yang et al.
patent: 5162064 (1992-11-01), Kim et al.
patent: 5172751 (1992-12-01), Croat
patent: 5240513 (1993-08-01), McCallum et al.
Branagan Daniel J.
McCallum R. William
Iowa State University & Research Foundation, Inc.
Sheehan John
Timmer Edward J.
LandOfFree
Carbide/nitride grain refined rare earth-iron-boron permanent ma does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Carbide/nitride grain refined rare earth-iron-boron permanent ma, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Carbide/nitride grain refined rare earth-iron-boron permanent ma will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1278244