Patent US4158561A successfully refreshed from Google Patents.
US4158561A
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Method for preparing oxide coated microlamination particles
Assignee: ABB Inc USA
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Filing: 1978-04-14
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Granted: 1979-06-19
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Expires: 1998-04-14
Abstract
Abstract A method for preparing oxide coated microlaminations characterized by heating microlamination particles at a temperature of about 1375 DEG in an atmosphere having a dew point of 55 DEG to 85 DEG F. and an air-to-natural gas ratio of from about 10.5:1 to about 8:1 for a time sufficient to decarburize the particles to less than 0.005% carbon and to form on the particle surfaces an oxide coating having a thickness of from about 0.01 to about 0.10 mils.
Inventors
- 👤 Norman M. Pavlik
- 👤 John Sefko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:26
CPC Classifications
C; C21; C21D; C21D3/00; C21D3/02; C21D3/04; B; B22; B22F; B22F1/00; B22F1/14; B22F1/145; B22F9/00; B22F9/02; B22F9/04; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/20; H01F1/22; H01F1/24; B22F2009/045; B22F2009/046
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
104 words
A method of preparing insulated microlamination particles for use as electrical components, comprising the steps of (a) placing a plurality of particles of microlaminations in a furnace which particles are substantially of an elongated rectangular cross-section and of ferrous alloy, and (b) heating the particles to a temperature range of from about 1350° to about 1450° F. in an atmosphere having an air to natural gas ratio of from about 10.5:1 to about 8:1 for sufficient time to decarburize the particles to less than 0.005% carbon and to form on the particle surfaces an oxide coating of from about 0.01 to about 0.10 mils.
Claim 2
Independent Claim
104 words
A method of preparing insulated microlamination particles for use as electrical components, comprising the steps of (a) placing a plurality of particles of microlaminations in a furnace which particles are substantially of an elongated rectangular cross-section and of ferrous alloy, and (b) heating the particles to a temperature range of from about 1350° to about 1450° F. in an atmosphere having an air to natural gas ratio of from about 10.5:1 to about 8:1 for sufficient time to decarburize the particles to less than 0.005% carbon and to form on the particle surfaces an oxide coating of from about 0.01 to about 0.10 mils.
Claim 3
Dependent Claim
19 words
The method of claim 1 in which the atmosphere has a dew point of from 55° to 85° F.
Claim 4
Dependent Claim
16 words
The method of claim 2 in which the particles are heated for at least 5 minutes.
Claim 5
Dependent Claim
27 words
The method of claim 3 in which the air to natural gas ratio is from 9:1 to 10.5:1 and the dew point is 70° to 80° F.
Claim 6
Dependent Claim
11 words
The method of claim 4 in which the ratio is 9.5:1.
Claim 7
Dependent Claim
22 words
The method of claim 5 in which the due point is about 76° F. and the furnace temperature is about 1375° F.
Claim 8
Independent Claim
109 words
A method of preparing compact cores of insulated microlamination particles for use as electrical components, comprising the steps of (a) forming microlaminations from thin, flat strips of ferrous alloys and of substantially rectangular shape, (b) heating said microlaminations in a temperature range of from about 1350° to 1450° F. in an atmosphere having an air to natural gas ratio of from about 10.5:1 to 8:1 for sufficient time to decarburize the particles to less than 0.005% carbon and to form on the particle surfaces an oxide coating of from about 0.01 to about 0.10 mils, and (c) compressing said microlaminations into a solidified configuration of the desired core component.
Claim 9
Independent Claim
109 words
A method of preparing compact cores of insulated microlamination particles for use as electrical components, comprising the steps of (a) forming microlaminations from thin, flat strips of ferrous alloys and of substantially rectangular shape, (b) heating said microlaminations in a temperature range of from about 1350° to 1450° F. in an atmosphere having an air to natural gas ratio of from about 10.5:1 to 8:1 for sufficient time to decarburize the particles to less than 0.005% carbon and to form on the particle surfaces an oxide coating of from about 0.01 to about 0.10 mils, and (c) compressing said microlaminations into a solidified configuration of the desired core component.
Claim 10
Dependent Claim
19 words
The method of claim 7 in which the atmosphere has a dew point of from 55° to 85° F.
Claim 11
Dependent Claim
16 words
The method of claim 8 in which the air to gas ratio is 9:1 to 10.5:1.
Claim 12
Dependent Claim
22 words
The method of claim 9 in which the dew point is about 76° F. and the furnace temperature is about 1375° F.
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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) | 1982-06-18 | 1982-12-18 | 1983-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-06-18 | 1986-12-18 | 1987-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-06-18 | 1990-12-18 | 1991-06-19 | $7700.00 | Window Closed / Lapsed |