US3884729A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of providing an aluminum coating on a steel substrate
Assignee: British Steel Corp
•
Filing: 1973-11-01
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Granted: 1975-05-20
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Expires: 1993-11-01
Abstract
Abstract A method of providing a surface of a steel substrate with an aluminum coating, the said method comprising coating the said surface of the steel substrate with a layer of metal, coating the said metal layer with a layer containing aluminium powder, the aluminium powder forming an alloy with the steel substrate at a predetermined elevated temperature, compacting the said metal and powder layers to the substrate, effecting a cold reduction, and effecting a subsequent annealing heat treatment to make the metal and powder layers adhere tightly to the substrate, and thus provide the substrate with the said aluminium coating, the metal layer serving to control nucleation of the said alloy which is formed at the said predetermined elevated temperature.
Inventors
- 👤 Albert Edward Jackson
- 👤 Ernest Wynne Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 00:19
CPC Classifications
C; C23; C23C; C23C10/00; C23C10/28; C23C10/34; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/4998; Y10T29/49982; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12028; Y10T428/12063; Y10T428/12139; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12951; Y10T428/12958; Y10T428/12965
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
95 words
IN A METHOD OF PROVIDING A SURFACE OF A STEEL SUBSTRATE WITH AN ALUMINIUM COATING, THE SAID METHOD COMPRISING ELECTROPLATING THE SAID SURFACE OF THE STEEL SUBSTRATE WITH ALAYER OF IRON, COATING THE IRON LAYER WITH A LAYER CONTAINING ALUMINIUM POWDER, AND COMPACTING THE SAID IRON AND POWDER LAYERS TO THE SUBSTRATE, THE IMPROVEMENT WHICH CONSISTS OF SUBSEQUENTLY EFFECTING A COLD REDUCTION WHICH REDUCES THE GAUGE OF THE SO-CALLED SUBSTRATE BY AT LEAST 30 PERCENT, AND EFFECTING A SUBSEQUENT RECRYSTALLISATION ANNEALING HEAT TREATMENT TO MAKE THE IRON AND POWDER LAYERS ADHERE TIGHTLY TO THE SUBSTRATE.
Claim 2
Dependent Claim
95 words
IN A METHOD OF PROVIDING A SURFACE OF A STEEL SUBSTRATE WITH AN ALUMINIUM COATING, THE SAID METHOD COMPRISING ELECTROPLATING THE SAID SURFACE OF THE STEEL SUBSTRATE WITH ALAYER OF IRON, COATING THE IRON LAYER WITH A LAYER CONTAINING ALUMINIUM POWDER, AND COMPACTING THE SAID IRON AND POWDER LAYERS TO THE SUBSTRATE, THE IMPROVEMENT WHICH CONSISTS OF SUBSEQUENTLY EFFECTING A COLD REDUCTION WHICH REDUCES THE GAUGE OF THE SO-CALLED SUBSTRATE BY AT LEAST 30 PERCENT, AND EFFECTING A SUBSEQUENT RECRYSTALLISATION ANNEALING HEAT TREATMENT TO MAKE THE IRON AND POWDER LAYERS ADHERE TIGHTLY TO THE SUBSTRATE.
Claim 3
Dependent Claim
39 words
A method as claimed in claim 1 in which, after compacting the said iron and powder layers and before effecting the cold reduction, the compacted substrate is subjected to an additional heat treatment in the range 300* to 500*C.
Claim 4
Dependent Claim
22 words
A method as claimed in claim 1 in which the reduction in gauge is in the range of 50 - 90 percent.
Claim 5
Dependent Claim
23 words
A method as claimed in claim 1 in which the original substrate has a gauge in the range 0.1 inch to 0.04 inch.
Claim 6
Dependent Claim
24 words
A method as claimed in claim 1 in which the recrystallisation anneal is effected at a temperature within the range of 500* to 550*C.
Claim 7
Dependent Claim
47 words
A method as claimed in claim 1 wherein compaction is effected by passing the coated substrate between a pair of rollers, the substrate, prior to passing between the rollers, being wetted with a liquid which reduces the extent to which the said rollers dislodge the aluminium powder.
Claim 8
Dependent Claim
41 words
A method as claimed in claim 1 in which the powder layer is made up of aluminium particles which are applied to the substrate in an electrostatically charged condition, the average particle size of the aluminium particles not exceeding 40 microns.
Claim 9
Dependent Claim
68 words
A method as claimed in claim 1 in which the powder layer contains aluminium powder whose average particle size does not exceed 40 microns and also contains a finely divided silicious material which causes the aluminium powder to flow substantially more readily than it would in the absence of the silicious material, the silicious material constituting not more than 0.5 percent by weight of the said powder layer.
Claim 10
Dependent Claim
27 words
A method as claimed in claim 8 in which the silicious material comprises particles of silica each of which has been provided with an hydrophobic organic coating.
Claim 11
Dependent Claim
24 words
A method as claimed in claim 1 in which the powder layer is applied to the steel substrate in the form of a slurry.
Claim 12
Dependent Claim
13 words
A method as claimed in claim 10 in which the slurry contains silica.
Claim 13
Dependent Claim
17 words
A method as claimed in claim 10 in which the slurry contains a water soluble cellulose ether.
Claim 14
Dependent Claim
14 words
A method as claimed in claim 10 in which the slurry contains a chromate.
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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) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |