Claims
- 1. A substantially lithium-free aluminum base alloy product having improved combinations of elongation and fracture toughness in an aged condition, the aluminum alloy product comprising:
- (a) at least 0.5 wt. % magnesium;
- (b) 0.01 to 1 ppm Na;
- (c) 0.01 to 1 ppm K;
- (d) less than 0.1 ppm Rb; and
- (e) less than 0.1 ppm Cs, the remainder comprising aluminum, the amount of Na, K, Rb and Cs measured by GDMS;
- said product in an aged condition having:
- (i) a grain boundary, region substantially free of liquid phase eutectics comprised of Na and K that form embrittlement phases at room temperature; and
- (ii) an increase in fracture toughness compared to an aluminum magnesium alloy having greater amounts of Na, K, Rb and Cs.
- 2. The product in accordance with claim 1 wherein Mg is at least 1 wt. %.
- 3. The product in accordance with claim 1 wherein said product contains less than 0.1 ppm hydrogen.
- 4. The product in accordance with claim 1 wherein said product contains less than 1 ppm chlorine.
- 5. A substantially lithium-free aluminum base alloy wrought product having improved combinations of elongation and fracture toughness in an aged condition, the aged aluminum alloy product comprising:
- (a) at least 0.5 wt. % magnesium;
- (b) 0.01 to 1 ppm Na;
- (c) 1 ppm max. K;
- (d) less than 0.1 ppm Rb; and
- (e) less than 0.1 ppm Cs, the remainder comprising aluminum, the amount of Na, K, Rb and Cs measured by GDMS;
- said product when in an aged condition having:
- (i) a grain boundary region substantially free of liquid phase eutectics comprised of Na and K that from embrittlement phases at room temperature; and
- (ii) an increase in fracture toughness compared to an aluminum magnesium alloy having greater amounts of Na, K, Rb and Cs.
- 6. A substantially lithium-free aluminum base alloy product having improved combinations of elongation and fracture toughness in an aged condition, the aluminum alloy product formed from a cast material and comprising:
- (a) at least 0.5 wt. % magnesium;
- (b) 1 ppm max. Na;
- (c) 0.01 to 1 ppm K;
- (d) less than 0.1 ppm Rb; and
- (e) less than 0.1 ppm Cs, the remainder comprising aluminum, the amount of Na, K, Rb and Cs measured by GDMS;
- said aged product in an aged condition having:
- (i) a grain boundary region substantially free of liquid phase eutectics comprised of Na and K that form embrittlement phases at room temperature; and
- (ii) an increase in fracture toughness compared to an aluminum magnesium alloy having greater amounts of Na, K, Rb and Cs.
- 7. A substantially lithium-free aluminum base alloy cast product capable of having improved combinations of elongation and fracture toughness in an aged condition, the aluminum alloy product comprising:
- (a) at least 0.5 wt. % magnesium;
- (b) about 0.01 to 1 ppm Na;
- (c) about 0.01 to 1 ppm K;
- (d) less than 0.1 ppm Rb; and
- (e) less than 0.1 ppm Cs, the remainder comprising aluminum, the amount of Na, K, Rb and Cs measured by GDMS;
- said product in said aged condition having:
- (i) a grain boundary region substantially free of liquid phase eutectics comprised of Na and K that form embrittlement phases at room temperature; and
- (ii) an increase in fracture toughness compared to an aluminum magnesium alloy having greater amounts of Na, K, Rb and Cs.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional of U.S. application Ser. No. 08/076,117, filed Jun. 14, 1993, now U.S. Pat. No. 5,422,066, issued Jun. 6, 1995, which is a continuation-in-part of U.S. application Ser. No. 07/946,245, filed Sep. 17, 1992 (now abandoned), and a continuation-in-part of U.S. application Ser. No. 07/771,907, filed Oct. 4, 1991, now U.S. Pat. No. 5,320,803, issued Jun. 14, 1994, both of which were continuations-in-part of U.S. application Ser. No. 07/328,364, filed Mar. 24, 1989, now U.S. Pat. No. 5,085,830, issued Feb. 4, 1992. The disclosures of these applications are hereby incorporated by reference.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
3895937 |
Gjosteen et al. |
Jul 1975 |
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Foreign Referenced Citations (1)
Number |
Date |
Country |
130985 |
Jul 1946 |
AUX |
Divisions (1)
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Number |
Date |
Country |
Parent |
76117 |
Jun 1993 |
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Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
946245 |
Sep 1992 |
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Parent |
328364 |
Mar 1989 |
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