US3658587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical insulation coating saturated with magnesium and/or calcium ions
Assignee: Allegheny Ludlum Corp
•
Filing: 1970-01-02
•
Granted: 1972-04-25
•
Expires: 1990-01-02
Abstract
Abstract A composition for providing an electrically insulative coating on electrical alloys having a high permeability and a low core loss which consists essentially of an aqueous solution containing ammonium ions, phosphate ions, chromate ions and a substantially saturated level of Group II A metal ions from at least one metal in Group II A of the periodic table, which are at least in part provided as the oxide, hydroxide, carbonate, bicarbonate and/or chromate of the Group II A metal or metals. A method for providing an electrically insulative coating on an electrical alloy having a high permeability and a low core loss comprising the steps of coating the alloy with the composition of this invention and curing the coating. A composite article comprising at least one layer of an electrical alloy having a high permeability and a low core loss and at least one layer of a substantially water insoluble, electrically insulative coating which is comprised of a saturated level of Group II A metal cations and anionic polymeric chains of chromium, oxygen and phosphorus atoms.
Inventors
- 👤 Clarence L Miller Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:45
CPC Classifications
H; H01; H01B; H01B3/00; H01B3/02; H01B3/025; C; C23; C23D; C23D5/00; C23D5/10; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/147; H01F1/14766; H01F1/14775; H01F1/14783; H01F27/00; H01F27/24; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265; Y10T428/31504; Y10T428/31678
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
41 words
A composition according to claim 1 wherein said ions are proportionately present in said aqueous solution as 9-15 mole percent ammonium ions, 30-55 mole percent phosphate ions, 11-20 mole percent chromate ions and 25-35 mole percent Group II A metal ions.
Claim 2
Dependent Claim
16 words
A composition according to claim 2 wherein said GROUP II A metal ions are calcium ions.
Claim 3
Dependent Claim
16 words
A composition according to claim 2 wherein said Group II A metal ions are magnesium ions.
Claim 4
Dependent Claim
36 words
A composition according to claim 1 wherein said Group II A metal ions are magnesium ions and wherein said magnesium ions are proportionately present in said aqueous solution as 25 - 35 mole percent magnesium ions.
Claim 5
Independent Claim
146 words
A method for providing an electrically insulative coating on an electrical alloy having a high permeability and a low core loss, which comprises, the steps of: coating said alloy with an aqueous solution containing ammonium ions, phosphate ions, chromate ions and a substantially saturated level of Group II A metal ions from the group consisting of magnesium ions and calcium ions and curing said coating so as to render it substantially water insoluble; said ions being proportionately present in said aqueous solution as 6 - 18 mole percent ammonium ions, 21 -63 mole percent phosphate ions, 8 -24 mole percent chromate ions and 15 -45 mole percent Group II A metal ions; at least 1 mole percent of said Group II A metal ions being provided from a compound of said Group II A metal from the group consisting of oxides, hydroxides, carbonates, bicarbonates and chromates.
Claim 6
Dependent Claim
12 words
A method according to claim 6 wherein said electrical alloy contains iron.
Claim 7
Dependent Claim
41 words
A method according to claim 7 wherein said ions are proportionately present in said aqueous solution as 9-15 mole percent ammonium ions, 30-55 mole percent phosphate ions, 11-20 mole percent chromate ions and 25-35 mole percent Group II A metal ions.
Claim 8
Dependent Claim
16 words
A method according to claim 7 wherein said Group II A metal ions are calcium ions.
Claim 9
Dependent Claim
16 words
A method according to claim 7 wherein said Group II A metal ions are magnesium ions.
Claim 10
Dependent Claim
25 words
A method according to claim 10 wherein said magnesium ions are proportionately present in said aqueous solution as 25 - 35 mole percent magnesium ions.
Claim 11
Dependent Claim
40 words
A method according to claim 6 wherein said coating is cured by heating said metallic surface at a temperature of from about 400* F to about 1,900* F for a period of from about 2 seconds to about 4 hours.
Claim 12
Dependent Claim
13 words
A method according to claim 6 wherein said electrical alloy is silicon steel.
Claim 13
Dependent Claim
190 words
A composite article comprising at least one layer of an electrical alloy having a high permeability and a low core loss and at least one layer of a substantially water insoluble, cured, electrically insulative coating adhered to said electrical alloy; said coating being comprised of a saturated level of Group II A metal cations from the group consisting of magnesium cations and calcium cations, and anionic polymeric chains of chromium, oxygen and phosphorus atoms; said coating having been formed from an aqueous solution of ammonium ions, phosphate ions, chromate ions and a substantially saturated level of Group II A metal ions from the group consisting of magnesium ions and calcium ions, wherein said ions were proportionately present in said aqueous solution as 6 - 18 mole percent ammonium ions, 21 - 63 mole percent phosphate ions, 8 - 24 mole percent chromate ions and 15 - 45 mole perCent Group II A metal ions, and wherein at least 1 mole percent of said Group II A metal ions were provided from a compound of said Group II A metal from the group consisting of oxides, hydroxides, carbonates, bicarbonates and chromates.
Claim 14
Dependent Claim
13 words
A composite article according to claim 14 wherein said electrical alloy contains iron.
Claim 15
Dependent Claim
17 words
A composite article according to claim 15 wherein said Group II A metal cations are calcium cations.
Claim 16
Dependent Claim
17 words
A composite article according to claim 15 wherein said Group II A metal cations are magnesium cations.
Claim 17
Dependent Claim
17 words
A composite article according to claim 15 wherein said coating is at least about 0.04 mil thick.
Claim 18
Dependent Claim
17 words
A composite article according to claim 18 wherein said coating is less than about 0.3 mil thick.
Claim 19
Dependent Claim
29 words
A composite article according to claim 15 wherein said Group II A metal cations are magnesium cations and wherein said coating is between about 0.06 and 0.2 mil thick.
Claim 20
Dependent Claim
27 words
A composite article according to claim 15 having a plurality of alloy layers with a layer of coating electrically insulating each alloy layer from adjacent alloy layers.
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) | 1975-04-25 | 1975-10-25 | 1976-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-25 | 1979-10-25 | 1980-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-25 | 1983-10-25 | 1984-04-25 | $7700.00 | Window Closed / Lapsed |