Patent US3620716A successfully refreshed from Google Patents.
US3620716A
Expired / Lapsed
US
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Magnesium removal from aluminum alloy scrap
Assignee: Alcoa Corp
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Filing: 1969-05-27
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Granted: 1971-11-16
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Expires: 1989-05-27
Abstract
Abstract Magnesium can be removed from secondary aluminum by contacting the melted metal with an effective amount of a flux containing potassium aluminum fluoride. This flux offers cost advantages over the known aluminum fluoride flux.
Inventors
- 👤 Paul D Hess
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:21
CPC Classifications
C; C22; C22B; C22B21/00; C22B21/06; C22B21/062; C22C; C22C1/00; C22C1/02; C22C1/026
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
64 words
maintaining said flux in contact with said molten body for a period of time of up to 10 hours to cause at least a substantial portion of the magnesium in said molten body to be removed from said molten body by reaction with said flux so that a magnesium-containing reaction product floats on the surface of said molten body in a skim layer, and
Claim 2
Dependent Claim
17 words
The method according to claim 1 wherein said flux contains at least 25 percent potassium aluminum fluoride.
Claim 3
Dependent Claim
10 words
said flux contains at least 50 percent potassium aluminum fluoride,
Claim 4
Dependent Claim
20 words
said molten body of aluminum is at a temperature of at least 1,400* F. when said flux is applied thereto,
Claim 5
Dependent Claim
7 words
The method according to claim 1 wherein:
Claim 6
Dependent Claim
9 words
thereafter separating said skim layer from said molten body.
Claim 7
Dependent Claim
23 words
said flux is applied in an amount of from 5 to 6 1/2 pounds flux per pound of magnesium in said melt, and
Claim 8
Dependent Claim
37 words
said flux is maintained in contact with said molten body for a period of from 3 to 6 hours while said molten body and said flux are stirred together periodically at intervals not exceeding a half hour.
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) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |