US4464199A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aluminum powder alloy product for high temperature application
Assignee: Alcoa Corp
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Filing: 1983-01-20
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Granted: 1984-08-07
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Expires: 2003-01-20
Abstract
Abstract Aluminum alloy atomized powder containing 4 to 15% iron and 1 to 12% cerium or other rare earth metal, when properly compacted and shaped into a useful article, exhibits very high strength at relatively high temperatures. The iron content exceeds the cerium or rare earth metal content, and the powder may contain refractory elements such as W, Mo and others. The powder is produced by atomizing alloyed molten aluminum, preferably in a nonoxidizing atmosphere, and is compacted to a density approaching 100% under controlled conditions including controlled temperature conditions. The alloy may be subsequently shaped by conventional forging, extruding or rolling processes.
Inventors
- 👤 Gregory J. Hildeman
- 👤 Robert E. Sanders, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:59
CPC Classifications
B; B22; B22F; B22F3/00; B22F3/12; B22F3/14; Y; Y10; Y10S; Y10S75/00; Y10S75/95
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
97 words
A method of producing an improved aluminum article having high strength at elevated temperatures, comprising the steps: (a) providing aluminum alloy particulate consisting essentially of 4 to 15% iron, 1 to 12% rare earth metal, balance aluminum and impurities and incidental elements, the weight ratio of iron to rare earth metal falling within the range of 0.5 to 5:1; and (b) compacting said powder under vacuum at a pressure of one torr or less and elevated temperature conditions wherein said powders are compacted to at least 95% of full density at a temperature greater than 650° F.
Claim 2
Independent Claim
97 words
A method of producing an improved aluminum article having high strength at elevated temperatures, comprising the steps: (a) providing aluminum alloy particulate consisting essentially of 4 to 15% iron, 1 to 12% rare earth metal, balance aluminum and impurities and incidental elements, the weight ratio of iron to rare earth metal falling within the range of 0.5 to 5:1; and (b) compacting said powder under vacuum at a pressure of one torr or less and elevated temperature conditions wherein said powders are compacted to at least 95% of full density at a temperature greater than 650° F.
Claim 3
Dependent Claim
22 words
The improvement according to claim 1 wherein the rare earth metal is selected from the group consisting of cerium and Misch metal.
Claim 4
Dependent Claim
18 words
The method according to claim 1 wherein said particulate contains from above 7% to 12% rare earth element.
Claim 5
Dependent Claim
16 words
The method according to claim 1 wherein said particulate contains from over 12% to 15% iron.
Claim 6
Dependent Claim
23 words
The method according to claim 1 wherein the ratio of iron to rare earth element ranges from about 0.5:1 to less than 1.2:1.
Claim 7
Dependent Claim
22 words
The method according to claim 1 wherein the ratio of iron to rare earth element ranges from above 4.4:1 to about 5:1.
Claim 8
Dependent Claim
36 words
The improvement according to claim 1 wherein said particulate additionally contains one or more elements from the group of up to 2.5% tungsten, up to 2.5% tantalum, up to 1.5% molybdenum and up to 1.5% niobium.
Claim 9
Dependent Claim
20 words
The improvement according to claim 1 wherein said particulate is produced by atomizing a superheated melt in a nonoxidizing atmosphere.
Claim 10
Dependent Claim
13 words
The improvement according to claim 8 wherein said nonoxidizing atmosphere is flue gas.
Claim 11
Dependent Claim
20 words
The improvement according to claim 1 wherein said vacuum compaction is effected at a temperature of at least 700° F.
Claim 12
Dependent Claim
16 words
The improvement according to claim 1 wherein said aluminum particulate contains less than 0.6% aluminum oxide.
Claim 13
Dependent Claim
25 words
The improvement according to claim 1 wherein substantially concurrently with said vacuum compaction the compact is upset equivalent to a reduction of at least 25%.
Claim 14
Dependent Claim
35 words
The method according to claim 1 wherein subsequent to said vacuum compaction the compact is worked equivalent to a reduction of at least 25% at a temperature within the range of 550° to 850° F.
Claim 15
Dependent Claim
42 words
The improvement according to claim 1 wherein said improved article exhibits high strength at elevated temperatures characterized by a yield strength of at least 30,000 psi and elongation of at least 5% at 450° F. after 1000 hours exposure to said temperature.
Claim 16
Independent Claim
150 words
A method of producing an improved aluminum article having high strength at elevated temperatures, comprising the steps: (a) providing atomized aluminum alloy powder consisting essentially of 4 to 15% iron, 1 to 12% of at least one metal from the group consisting of cerium and Misch metal, balance aluminum and impurities and incidental elements, the weight ratio of iron to cerium plus Misch metal ranging between 0.5 and 5:1; (b) vacuum compacting said powder at a pressure not exceeding 0.1 torr and a temperature of 700° to 850° F. under sufficient compaction to produce a compact at least 98% of full density; and (c) working said compact at a temperature of 550° to 850° F. equivalent to a cross-sectional reduction of at least 25% to produce said article characterized by a yield strength of at least 35,000 psi and elongation of at least 51/2% at a temperature of 450° F.
Claim 17
Independent Claim
150 words
A method of producing an improved aluminum article having high strength at elevated temperatures, comprising the steps: (a) providing atomized aluminum alloy powder consisting essentially of 4 to 15% iron, 1 to 12% of at least one metal from the group consisting of cerium and Misch metal, balance aluminum and impurities and incidental elements, the weight ratio of iron to cerium plus Misch metal ranging between 0.5 and 5:1; (b) vacuum compacting said powder at a pressure not exceeding 0.1 torr and a temperature of 700° to 850° F. under sufficient compaction to produce a compact at least 98% of full density; and (c) working said compact at a temperature of 550° to 850° F. equivalent to a cross-sectional reduction of at least 25% to produce said article characterized by a yield strength of at least 35,000 psi and elongation of at least 51/2% at a temperature of 450° F.
Claim 18
Dependent Claim
48 words
The improvement according to claim 15 wherein said aluminum alloy powder additionally contains one or more elements from the group of up to 2.5% tungsten, up to 2.5% tantalum, up to 1.5% molybdenum and up to 1.5% niobium, the combined total of said additional elements not exceeding 5%.
Claim 19
Dependent Claim
54 words
The improvement according to claim 15 wherein, prior to said compaction, said powder is isostatically compacted at room temperature to a cohesive shape exhibiting at least 65% of full density which said isostatically compacted cohesive shape is then compacted at said elevated temperature and vacuum condition according to said step (b) of claim 15.
Claim 20
Dependent Claim
24 words
The improvement according to claim 15 wherein said working of said step (c) is equivalent to a reduction of at least 50% in cross-section.
Claim 21
Dependent Claim
10 words
The aluminum article produced by the method of claim 1.
Claim 22
Dependent Claim
10 words
The aluminum article produced by the method of claim 3.
Claim 23
Dependent Claim
10 words
The aluminum article produced by the method of claim 4.
Claim 24
Dependent Claim
10 words
The aluminum article produced by the method of claim 5.
Claim 25
Dependent Claim
10 words
The aluminum article produced by the method of claim 6.
Claim 26
Dependent Claim
10 words
The aluminum article produced by the method of claim 7.
Claim 27
Dependent Claim
10 words
The aluminum article produced by the method of claim 15.
Claim 28
Dependent Claim
10 words
The aluminum article produced by the method of claim 16.
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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) | 1987-08-07 | 1988-02-06 | 1988-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-07 | 1992-02-06 | 1992-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-07 | 1996-02-06 | 1996-08-07 | $7700.00 | Window Closed / Lapsed |