Patent US4115158A successfully refreshed from Google Patents.
US4115158A
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US
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Process for producing soft magnetic material
Assignee: KEYSTONE CARBON COMPANY A PA CORP
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Filing: 1977-10-03
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Granted: 1978-09-19
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Expires: 1997-10-03
Abstract
Abstract A process for producing a phosphorus-bearing soft magnetic material. The process includes the steps of: blending iron powder and ferro-phosphorus powder into a mixture containing from 0.4 to 1.25% phosphorus; pressing said blended mixture into a compact; and sintering said compact in a non-oxidizing atmosphere. The iron and ferro-phosphorus powder respectively have no more than 0.02 and 0.2% calcium. The ferro-phosphorus powder has from 12 to 30% phosphorus.
Inventors
- 👤 Orville W. Reen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:41
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/02; C22C33/0207; C22C33/0214; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/20; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/928
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
79 words
In a process for producing a phosphorus-bearing soft magnetic material, which process includes the step of: blending iron powder and ferro-phosphorus powder into a mixture containing from 0.4 to 1.25% phosphorus; pressing said blended mixture into a compact; and sintering said compact in a non-oxidizing atmosphere; the improvement comprising the step of blending ferro-phosphorus powder having no more than 0.2% calcium with iron powder having no more than 0.02% calcium, said ferro-phosphorus powder having from 12 to 30% phosphorus.
Claim 2
Dependent Claim
79 words
In a process for producing a phosphorus-bearing soft magnetic material, which process includes the step of: blending iron powder and ferro-phosphorus powder into a mixture containing from 0.4 to 1.25% phosphorus; pressing said blended mixture into a compact; and sintering said compact in a non-oxidizing atmosphere; the improvement comprising the step of blending ferro-phosphorus powder having no more than 0.2% calcium with iron powder having no more than 0.02% calcium, said ferro-phosphorus powder having from 12 to 30% phosphorus.
Claim 3
Dependent Claim
15 words
The improvement according to claim 1, wherein said ferro-phosphorus has no more than 0.15% calcium.
Claim 4
Dependent Claim
16 words
The improvement according to claim 1, wherein said iron powder has no more than 0.015% calcium.
Claim 5
Dependent Claim
14 words
The improvement according to claim 1, wherein said ferro-phosphorus has at least 18% phosphorus.
Claim 6
Dependent Claim
43 words
A phosphorus-bearing soft magnetic material characterized by a magnetizing force to reach 10 kilogauss of no more than 2.0 oersteds, and a coercive force from 10 kilogauss of no more than 0.9 oersted, and made in accordance with the process of claim 1.
References Cited (Backward Citations)
US4047983A
Cited
US4030913A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-09-18 | 1982-03-20 | 1982-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-18 | 1986-03-20 | 1986-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-18 | 1990-03-20 | 1990-09-19 | $7700.00 | Window Closed / Lapsed |