US4892596A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making fully dense anisotropic high energy magnets
Assignee: Eastman Kodak Co
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Filing: 1988-02-23
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Granted: 1990-01-09
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Expires: 2008-02-23
Abstract
Abstract A method of making anisotropic permanent magnets by extruding a rare earth magnetic alloy together with an oxygen-getter material at a temperature below the melting point of the alloy at an extrusion ratio of from 10:1 to 26:1.
Inventors
- 👤 Dilip K. Chatterjee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:47
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; H01F1/0576; Y; Y10; Y10S; Y10S72/00; Y10S72/70
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
67 words
A method of making anisotropic permanent magnets which comprises extruding a rare earth, transition metal, magnetic alloy together with an oxygen-getter material at a temperature of from about 600° C. to about 1000° C. at an extrusion ratio of from about 10:1 to about 26:1 said rare earth, transition metal, magnetic alloy and said oxygen-getter material being disposed within an extrusion zone in separate and discrete locations.
Claim 2
Independent Claim
67 words
A method of making anisotropic permanent magnets which comprises extruding a rare earth, transition metal, magnetic alloy together with an oxygen-getter material at a temperature of from about 600° C. to about 1000° C. at an extrusion ratio of from about 10:1 to about 26:1 said rare earth, transition metal, magnetic alloy and said oxygen-getter material being disposed within an extrusion zone in separate and discrete locations.
Claim 3
Dependent Claim
21 words
The process of claim 1 wherein the rate earth, transition metal, magnetic alloy is an alloy of neodymium, iron and boron.
Claim 4
Dependent Claim
20 words
The process of claim 2 wherein the main magnetic phase in the magnetic alloy is Nd 2 Fe 14 B.
Claim 5
Dependent Claim
31 words
The process of claim 1 wherein the oxygen-getter is disposed in a zone in the extrusion apparatus nearest the extrusion orifice at the leading surface of the rare earth magnetic alloy.
Claim 6
Dependent Claim
27 words
The process of claim 1 wherein the oxygen-getter material is selected from the group consisting of magnesium, calcium, a rare earth metal, titanium, tantalum and mixtures thereof.
Claim 7
Dependent Claim
11 words
The process of claim 5 wherein the oxygen-getter material is titanium.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-08 | 1993-07-10 | 1994-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-08 | 1997-07-10 | 1998-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-08 | 2001-07-10 | 2002-01-09 | $7700.00 | Window Closed / Lapsed |