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US5252144A Expired / Lapsed US ⏱️ 0.0 years remaining

Heat treatment process and soft magnetic alloys produced thereby

Assignee: Honeywell International Inc
•
Filing: 1991-11-04
•
Granted: 1993-10-12
•
Expires: 2011-11-04
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Abstract

Abstract The present invention relates to a novel heat treatment process, and the alloy products produced thereby. The heat treatment process includes heating an alloy at a temperature and for a time sufficient to cause crystallization, cooling the alloy at a rate greater than about 10° C. per minute, preferably greater than about 50° C. per minute, and most preferably greater than about 100° C. per minute. Alloys of many compositions and having either amorphous, surface crystallized or partially bulk crystallized structure may be beneficially treated. Alloy strips and cores heat treated according to the present invention display B-H loops which display a discontinuous change in slope at near zero field conditions. Alloy strips which have been heat treated according to the present invention display greatly increased resonant output voltages and are particularly useful as resonant markers in article surveillance systems. Cores which have been heat treated according to the present invention display constant permeabilities up to about 1 MHz and are particularly useful as EMI filters and high frequency transformers.

Inventors

  • 👤 Ronald J. Martis

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 11:55
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/22; G08B13/24; G08B13/2402; G08B13/2405; G08B13/2408; G01; G01V; G01V15/00; G08B13/2428; G08B13/2437; G08B13/2442; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/147; H01F1/153; H01F1/15308; H01F1/15333; H01F1/15341

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 81 words
A process comprising the steps of: providing a metal strip of a positive magnetostrictive alloy having at least one crystallization temperature and an essentially surface crystalline phase defining a major surface of said strip and an amorphous phase contiguous with said crystalline phase and remote from said major surface; heating said metal strip to a temperature between about 70% and about 99% of the first crystallization temperature; and cooling said heated metal strip at a rate greater than about 10° C./min.
Claim 2
Dependent Claim 81 words
A process comprising the steps of: providing a metal strip of a positive magnetostrictive alloy having at least one crystallization temperature and an essentially surface crystalline phase defining a major surface of said strip and an amorphous phase contiguous with said crystalline phase and remote from said major surface; heating said metal strip to a temperature between about 70% and about 99% of the first crystallization temperature; and cooling said heated metal strip at a rate greater than about 10° C./min.
Claim 3
Dependent Claim 27 words
The process of claim 1 wherein said heat treated metal strip displays a B-H loop which has an abrupt change in slope at near zero field conditions.
Claim 4
Dependent Claim 24 words
The process of claim 1 wherein said metal strip is annealed at a temperature between about 80% and about 90% of first crystallization temperature.
Claim 5
Dependent Claim 19 words
The process of claim 1 wherein said cooling is carried out at a rate of at least 50° C./min.
Claim 6
Dependent Claim 19 words
The process of claim 1 wherein said cooling is carried out at a rate of at least 100° C./min.
Claim 7
Dependent Claim 61 words
A process comprising the steps of: providing a core comprising an annealed amorphous alloy ribbon having a surface crystalline phase and a bulk amorphous phase; heating said core to a temperature between about 70% and about 99% of a first crystallization temperature of the amorphous alloy; and cooling said heat treated core so that said core displays a pinched B-H loop.
Claim 8
Dependent Claim 61 words
A process comprising the steps of: providing a core comprising an annealed amorphous alloy ribbon having a surface crystalline phase and a bulk amorphous phase; heating said core to a temperature between about 70% and about 99% of a first crystallization temperature of the amorphous alloy; and cooling said heat treated core so that said core displays a pinched B-H loop.
Claim 9
Dependent Claim 19 words
The process of claim 6 wherein said cooling is carried out at a rate of at least 10° C./min.
Claim 10
Dependent Claim 19 words
The process of claim 6 wherein said cooling is carried out at a rate of at least 50° C./min.
Claim 11
Dependent Claim 18 words
The process of claim 6 wherein said cooling is carried out at a rate of at 100° C./min.

References Cited (Backward Citations)

US4116728A Cited
US4116728B1 Cited
US4081298A Cited
US4221257A Cited
US4268325A Cited
US4219355A Cited
JPS562602A Cited
US4249969A Cited
US4298409A Cited
US4525222A Cited
DE3215263A1 Cited
US4482402A Cited
US4510489A Cited
US4510490A Cited
JPS6218008A Cited
US4823113A Cited
US4877464A Cited
JPS6329909A Cited
US4881989A Cited
US4834815A Cited
US4985088A Cited
JPH0375341A Cited
GB2233345A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-10-11 1997-04-12 1997-10-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-10-11 2001-04-12 2001-10-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-10-11 2005-04-12 2005-10-12 $7700.00 Window Closed / Lapsed

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