Aluminum-copper-lithium alloys
View Patent ↗Improved aluminum-copper-lithium alloys are disclosed. The alloys may include 3.4-4.2 wt. % Cu, 0.9-1.4 wt. % Li, 0.3-0.7 wt. % Ag, 0.1-0.6 wt. % Mg, 0.2-0.8 wt. % Zn, 0.1-0.6 wt. % Mn, and 0.01-0.6 wt. % of at least one grain structure control element, the balance being aluminum and incidental elements and impurities. The alloys achieve an improved combination of properties over prior art alloys.
1. A wrought aluminum alloy product consisting of:
3.4-4.2 wt. % Cu;
0.9-1.4 wt. % Li;
0.3-0.7 wt. % Ag;
0.1-0.6 wt. % Mg;
0.2-0.8 wt. % Zn;
0.1-0.6 wt. % Mn; and
0.05-0.15 wt. % Zr;
the balance being aluminum and incidental elements and impurities;
wherein the wrought aluminum alloy product realizes a longitudinal tensile yield strength of at least 86 ksi.
2. The wrought aluminum alloy product of claim 1 , wherein the wrought aluminum alloy product consists of:
3.6-4.1 wt. % Cu;
1.0-1.3 wt. % Li;
0.3-0.7 wt. % Zn;
0.4-0.6 wt. % Ag;
0.2-0.5 wt. % Mg;
0.1-0.4 wt. % Mn; and
0.05-0.15 wt. % Zr;
the balance being aluminum and incidental elements and impurities.
3. The wrought aluminum alloy product of claim 1 , wherein the wrought aluminum alloy product consists of:
3.7-4.0 wt. % Cu;
1.1-1.2 wt. % Li;
0.4-0.6 wt. % Zn;
0.4-0.6 wt. % Ag;
0.25-0.45 wt. % Mg;
0.2-0.4 wt. % Mn; and
0.05-0.15 wt. % Zr;
the balance being aluminum and incidental elements and impurities.
4. The wrought aluminum alloy product of any of claims 1 and 2 - 3 , wherein the wrought aluminum alloy product is in the form of an extrusion, and has an accumulated cold work of not greater than an equivalent of 4% stretch.
5. The wrought aluminum alloy product of claim 1 , wherein the impurities comprises Fe and Si, and wherein the wrought aluminum alloy product comprises not greater than 0.06 wt. % Si and not greater than 0.08 wt. % Fe.
6. The wrought aluminum alloy product of claim 1 , wherein the wrought aluminum alloy product is resistant to galvanic corrosion.
7. An airplane spar comprising the extruded aluminum alloy product of claim 4 .
8. An airplane stringer comprising the extruded aluminum alloy product of claim 4 .
9. The wrought aluminum alloy product of claim 1 , wherein the wrought aluminum alloy product realizes a longitudinal tensile yield strength of at least 88 ksi.
10. The wrought aluminum alloy product of claim 1 , wherein the wrought aluminum alloy product realizes a longitudinal tensile yield strength of at least 90 ksi.
11. The wrought aluminum alloy product of claim 1 , wherein the wrought aluminum alloy product realizes a longitudinal tensile yield strength of at least 91 ksi.
12. The wrought aluminum alloy product of claim 1 , wherein the wrought aluminum alloy product realizes a longitudinal tensile yield strength of at least 96 ksi.
13. The wrought aluminum alloy product of any of claim 1 or 9 - 12 , wherein the wrought aluminum alloy product realizes an L-T plane strain fracture toughness of at least 20 ksi√in.
14. The wrought aluminum alloy product of any of claim 1 or 9 - 12 , wherein the extruded aluminum alloy product realizes an L-T plane strain fracture toughness of at least 23 ksi√in.
15. The wrought aluminum alloy product of any of claim 1 or 9 - 12 , wherein the extruded aluminum alloy product realizes an L-T plane strain fracture toughness of at least 27 ksi√in.
16. The wrought aluminum alloy product of any of claim 1 or 9 - 12 , wherein the extruded aluminum alloy product realizes an L-T plane strain fracture toughness of at least 31 ksi√in.