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Patent US3958176A successfully refreshed from Google Patents.
US3958176A
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US
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Method for measuring suitability of aluminum for use in certain propellants
Assignee: United States Department of the Navy
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Filing: 1975-02-24
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Granted: 1976-05-18
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Expires: 1995-02-24
Abstract
Abstract The resistance of aluminum particles which contain aluminum oxide coatings is measured while the particles are being slowly heated. The resistance is plotted against temperature. If the resistance drops off to zero before the temperature reaches 660°C, the particles are undesirable for use as a fuel in certain rocket propellants.
Inventors
- 👤 Karl J. Kraeutle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:27
CPC Classifications
G; G01; G01R; G01R27/00; G01R27/02; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/043
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
70 words
A method for determining whether or not aluminum powder is desirable for use as a fuel in a rocket propellant comprising the steps of: a. simultaneously heating the powder at a controlled rate and monitoring the resistance and temperature of the powder; and b. determining whether or not the resistance of the powder approaches a low value before or after the powder has been heated to a temperature of 660°C.
Claim 2
Independent Claim
70 words
A method for determining whether or not aluminum powder is desirable for use as a fuel in a rocket propellant comprising the steps of: a. simultaneously heating the powder at a controlled rate and monitoring the resistance and temperature of the powder; and b. determining whether or not the resistance of the powder approaches a low value before or after the powder has been heated to a temperature of 660°C.
Claim 3
Dependent Claim
23 words
The method according to claim 1 wherein the powder is heated at a rate of from about 20° to about 25°C per minute.
Claim 4
Dependent Claim
17 words
The method according to claim 2 wherein said low value is between about 5 to 10 ohms.
References Cited (Backward Citations)
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Cited
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US3580049A
Cited
US3578756A
Cited
US3701278A
Cited
US3899919A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-05-18 | 1979-11-17 | 1980-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-18 | 1983-11-17 | 1984-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-18 | 1987-11-17 | 1988-05-18 | $7700.00 | Window Closed / Lapsed |