Rare earth-based permanent magnet

Details Rare earth-based permanent magnet Rare earth-based permanent magnet

1993-09-13

1995-04-11

Sheehan, John P.

Metal treatment

Process of modifying or maintaining internal physical...

Magnetic materials

419 12, H01F 1057

Patent

active

054054559

ABSTRACT:
Disclosed is a novel method for the preparation of a rare earth-based permanent magnet by the so-called two-alloy process in which powders of two kinds of rare earth-containing magnetic alloys each having a different composition from the other are blended together in a specified proportion and the powder blend is shaped in a magnetic field into a green body which is sintered. In the invention, the first magnetic alloy has a composition of the formula R.sub.2 T.sub.14 B, in which R is a rare earth element selected from the group consisting of neodymium, praseodymium, dysprosium and terbium and T is iron or a combination of iron and cobalt, while the second alloy has a composition of the formula R.sub.a Fe.sub.b Co.sub.c B.sub.d M.sub.e, in which R has the same meaning as defined above, M is an element selected from the group consisting of gallium, aluminum, copper, zinc, indium, silicon, phosphorus, sulfur, titanium, vanadium, chromium, manganese, germanium, zirconium, niobium, molybdenum, palladium, silver, cadmium, tin, antimony, hafnium, tantalum and tungsten, the subscript a is a positive number in the range from 15 to 40, b is zero or a positive number not exceeding 80, c is a positive number in the range from 5 to 85, d is a positive number not exceeding 20 and e is zero or a positive number not exceeding 20 with the proviso that a+b+c+d+e is 100, and the powders are blended in a weight proportion of 99:1 to 70:30.

REFERENCES:
patent: 4898625 (1990-02-01), Otsuka et al.
patent: 4968347 (1990-11-01), Ramesh et al.
patent: 5049203 (1991-09-01), Rukai et al.
J. F. Liu et al., `Magnetic Properties of Ga Doped NdFeCoB Sintered Magnets`, *table 1*, IEEE Transactions of Magnetics, vol. 26, No. 5, Sep. 1990, New York US, pp. 2640-2642.
Patent Abstracts of Japan, vol. 12, No. 379 (E-667)(3226) 11 Oct. 1988 & JP-63 127 505 (Taio Yuden Co., Ltd.) 31 May 1988 *abstract*.

Affiliated with

Also associated with

Rating

Rare earth-based permanent magnet does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Rare earth-based permanent magnet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rare earth-based permanent magnet will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1535919