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US4900587A
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Method for producing aluminum oxide coated iron-aluminum alloy powder
Assignee: Osram Sylvania Inc
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Filing: 1989-01-03
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Granted: 1990-02-13
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Expires: 2009-01-03
Abstract
Abstract A method is disclosed for producing aluminum oxide coated iron-aluminum alloy powder which comprises contacting iron-aluminum alloy powder of fine particle size with a liquid aluminum compound wherein the aluminum is hydrolyzable and adding water to the compound and the iron-aluminum alloy powder to form a slurry, removing essentially all of the liquid from the slurry to produce iron-aluminum alloy powder with a coating of hydrolyzed aluminum oxide, and firing the iron-aluminum alloy powder with the hydrolyzed aluminum oxide coating in a non-oxidizing atmosphere to produce iron-aluminum alloy powder with a coating of aluminum oxide.
Inventors
- 👤 Joseph E. Ritsko
- 👤 Walter A. Johnson
- 👤 Nelson E. Kopatz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:40
CPC Classifications
C; C23; C23C; C23C24/00; B; B22; B22F; B22F1/00; B22F1/16; C23C18/00; C23C18/02; C23C18/12; C23C18/1204; C23C18/1208; C23C18/1216; C23C18/1229; C23C18/1241; C23C18/125; C23C18/1275
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
97 words
A method for producing aluminum oxide coated iron-aluminum alloy powder, said method comprising: (a) contacting iron-aluminum alloy powder of fine particle size with a liquid aluminum compound wherein the aluminum is hydrolyzable and adding water to said compound and said iron-aluminum alloy powder to form a slurry; (b) removing essentially all of the liquid from said slurry to produce iron-aluminum alloy powder with a coating of hydrolyzed aluminum oxide; and (c) firing said iron-aluminum alloy powder with said hydrolyzed aluminum oxide coating in a non-oxidizing atmosphere to produce iron-aluminum alloy powder with a coating of aluminum oxide.
Claim 2
Independent Claim
97 words
A method for producing aluminum oxide coated iron-aluminum alloy powder, said method comprising: (a) contacting iron-aluminum alloy powder of fine particle size with a liquid aluminum compound wherein the aluminum is hydrolyzable and adding water to said compound and said iron-aluminum alloy powder to form a slurry; (b) removing essentially all of the liquid from said slurry to produce iron-aluminum alloy powder with a coating of hydrolyzed aluminum oxide; and (c) firing said iron-aluminum alloy powder with said hydrolyzed aluminum oxide coating in a non-oxidizing atmosphere to produce iron-aluminum alloy powder with a coating of aluminum oxide.
Claim 3
Dependent Claim
13 words
A method of claim 1 wherein said aluminum compound is an aluminum alkoxide.
Claim 4
Dependent Claim
12 words
A method of claim 2 wherein said aluminum compound is aluminum tri-(sec-butoxide).
Claim 5
Dependent Claim
28 words
A method of claim 1 wherein after said water is added to said slurry, said slurry is heated at a temperature of no greater than about 90° C.
Claim 6
Dependent Claim
22 words
A method of claim 1 wherein said non-oxidizing atmosphere is selected from the group consisting of argon, hydrogen, nitrogen, and mixtures thereof.
Claim 7
Dependent Claim
11 words
A method of claim 5 wherein said non-oxidizing atmosphere is argon.
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) | 1993-02-12 | 1993-08-14 | 1994-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-12 | 1997-08-14 | 1998-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-12 | 2001-08-14 | 2002-02-13 | $7700.00 | Window Closed / Lapsed |