Aluminum powder alloy product for high temperature application
AssigneeAluminum Company of America
InventorsGregory J. Hildeman, Robert E. Sanders, Jr.
Life of this patent
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Abstract
Aluminum alloy atomized powder containing 4 to 12% iron and 1 to 7% 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.
Claims30
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 12% iron, 1 to 7% rare earth metal, balance aluminum and impurities and incidental elements, the weight ratio of iron to rare earth metal falling within the range of 1.2 to 4.4:1;
- 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.degree. F.
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 12% iron, 1 to 7% 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 1.2 and 4.4:1;
- (b) vacuum compacting said powder at a pressure not exceeding 0.1 torr and a temperature of 700.degree. to 850.degree. F. under sufficient compaction to produce a compact at least 98% of full density;
- and
- (c) working said compact at a temperature of 550.degree. to 850.degree. 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.degree. F.
Dependencies are inferred from the claim text.