Patent EP0125752A2 successfully refreshed from Google Patents.
EP0125752A2
Expired / Lapsed
EP
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Bonded rare earth-iron magnets
Assignee: Magnequench International LLC
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Filing: 1984-03-06
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Granted: —
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Expires: 2004-03-06
Abstract
Abstract This invention discloses permanent bonded magnets of very finely crystalline, melt-spun, rare earth-iron alloys. They are formed by compacting particles of the alloys into compacts (12), which are then fixed in shape by suitable binding agents (22), and are then magnetized. The compacts (12) are magnetically isotropic.
Inventors
- 👤 Robert Weir Lee
- 👤 John Joseph Croat
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 16:44
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/047; H01F1/053; H01F1/055; H01F1/057; H01F1/0571; H01F1/0575; H01F1/0578
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
131 words
A permanent bonded magnet (30) formed of melt-spun alloy ribbon particles that have a very finely crystalline magnet phase, said alloy comprising one or more rare earth elements taken from the group consisting of neodymium, praseodymium, and mischmetals; the transition metal element, iron; and boron; characterised in that in said magnet the particles are maintained in a desired magnet shape (12) by a binding agent (22) interspersed therebetween; and the particles are magnetically isotropic and the magnet shape (12) may be magnetized in any desired direction in a suitable magnetic field (34) to form the bonded magnet (30); a said bonded magnet (30) with a particle compact density of at least 80% of the alloy density having a remanent magnetic energy product of at least nine megaGauss Oersted at magnetic saturation.
Claim 2
Dependent Claim
131 words
A permanent bonded magnet (30) formed of melt-spun alloy ribbon particles that have a very finely crystalline magnet phase, said alloy comprising one or more rare earth elements taken from the group consisting of neodymium, praseodymium, and mischmetals; the transition metal element, iron; and boron; characterised in that in said magnet the particles are maintained in a desired magnet shape (12) by a binding agent (22) interspersed therebetween; and the particles are magnetically isotropic and the magnet shape (12) may be magnetized in any desired direction in a suitable magnetic field (34) to form the bonded magnet (30); a said bonded magnet (30) with a particle compact density of at least 80% of the alloy density having a remanent magnetic energy product of at least nine megaGauss Oersted at magnetic saturation.
Claim 3
Dependent Claim
105 words
A permanent bonded magnet (30) according to claim 1, characterised in that said particles are particles of a friable, rapidly quenched, finely crystalline, melt-spun alloy ribbon (10), and said particles are fractured and compacted under pressure into a compact (12) with said magnet shape, in a die having the shape of said magnet, said fractured and compacted particles in the compact (12) then being fixed in said magnet shape by said binding agent (22): and said compact (12) being equally susceptible to magnetization in any desired direction in the presence of a magnetic field of suitable direction and magnitude to form a permanent magnet (30).
Claim 4
Dependent Claim
88 words
A permanent bonded magnet (30) according to claim 2, characterised in that said particles have a substantially brick-like shape and are spacially oriented substantially parallel to each other within regions of the compact (12) to achieve high compact densities and compact green strength; said compact (12) being equally susceptible to magnetization in any direction in an applied magnetic field of suitable strength and direction such that at a compact density of 80% of said alloy the magnet (30) formed has a magnetic remanence of at least six kiloGauss.
Claim 5
Dependent Claim
25 words
A permanent bonded magnet (30) according to claim 2 or 3, characterised in that said particles each consist of a plurality of individual fine crystals.
References Cited (Backward Citations)
No citation records indexed.
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