Patent US5091022A successfully refreshed from Google Patents.
US5091022A
Expired / Lapsed
US
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Manufacturing process for sintered fe-p alloy product having soft magnetic characteristics
Assignee: Sumitomo Metal Mining Co Ltd
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Filing: 1990-07-19
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Granted: 1992-02-25
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Expires: 2010-07-19
Abstract
Abstract There is disclosed a method for manufacturing intricate shaped magnetic parts having excellent soft magnetic characteristics which includes forming powders of Fe and P having particle sizes less than 45 μm; mixing 0.1 to 1.0% by weight P powder with Fe powder; adding a binder; injection-molding the mixture at 1200 kg/cm 2 ; removing the binder by heating; sintering the binder free part at 1200°-1400° C. for 30-180 min; and cooling the sintered part at a rate of less than 50° C./min.
Inventors
- 👤 Masakazu Achikita
- 👤 Akihito Ohtsuka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:29
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/02; C22C33/0257; C22C33/0264; C22C33/0271; B; B22; B22F; B22F3/00; B22F3/22; B22F3/225; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/20; H01F1/22; B22F2998/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
117 words
The method of manufacturing a sintered Fe-P powdered metal product having high magnetic permeability and excellent soft magnetic characteristics which comprises the steps of: preparing powders of Fe and P having particle sizes of less than 45 μm; preparing a mixture of Fe and P powders having from 0.1 to 1.0% by weight of P and the balance of Fe; mixing said Fe-P mixture with a binder to form a pellet for injection molding; injection molding said powder and binder mixture to form a desired product; removing the binder material from said injection molded product; sintering said binder free injection molded product; and cooling said product at a rate of less than 50° C./min. to ambient temperature.
Claim 2
Independent Claim
117 words
The method of manufacturing a sintered Fe-P powdered metal product having high magnetic permeability and excellent soft magnetic characteristics which comprises the steps of: preparing powders of Fe and P having particle sizes of less than 45 μm; preparing a mixture of Fe and P powders having from 0.1 to 1.0% by weight of P and the balance of Fe; mixing said Fe-P mixture with a binder to form a pellet for injection molding; injection molding said powder and binder mixture to form a desired product; removing the binder material from said injection molded product; sintering said binder free injection molded product; and cooling said product at a rate of less than 50° C./min. to ambient temperature.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein said Fe-P powder is mixed with a binder to form a mix of 40% by volume of binder material.
Claim 4
Dependent Claim
17 words
The method of claim 1 further including choosing the binder from either a polyethylene or a wax.
Claim 5
Dependent Claim
47 words
The method of claim 1 wherein: the Fe powder is prepared with a particle size of 5 μm; the mixture of Fe and P powders is prepared with 0.3% by weight of P; and the sintered product is cooled at a rate of 10° C. per minute.
Claim 6
Dependent Claim
47 words
The method of claim 1 wherein: the Fe powder is prepared with a particle size of 5 μm; the mixture of Fe and P powders is prepared with 0.5% by weight of P; and the sintered product is cooled at a rate of 10° C. per minute.
Claim 7
Dependent Claim
47 words
The method of claim 1 wherein: the Fe powder is prepared with a particle size of 5 μm; the mixture of Fe and P powders is prepared with 0.8% by weight of P; and the sintered product is cooled at a rate of 10° C. per minute.
Claim 8
Dependent Claim
33 words
The method of claim 1 wherein removing the binder material includes heating the injection molded product at a temperature of 300° C. in an oxygen free atmosphere to drive off the binder material.
Claim 9
Dependent Claim
32 words
The method of claim 1 wherein removing the binder material includes heating the injection molded product at a temperature of 300° C. in a nitrogen atmosphere to drive off the binder material.
Claim 10
Dependent Claim
24 words
The method of claim 1 wherein said injection molding of said powder and binder mixture is at a pressure of 1200 kg/cm 2 .
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-02-24 | 1995-08-26 | 1996-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-02-24 | 1999-08-26 | 2000-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-02-24 | 2003-08-26 | 2004-02-25 | $7700.00 | Window Closed / Lapsed |