Abstract: An improved aluminum based alloy containing lithium is disclosed. The alloy may be provided as extruded aluminum-copper-lithium products having improved combinations of strength, fracture toughness, corrosion resistance and relatively low density. The extrusion alloy may include from 2.6 to 3.0 weight percent Cu, from 1.4 to 1.75 weight percent Li, from 0.0 to 0.25 weight percent Mn, from 0.10 to 0.45 weight percent Mg, from 0.05 to 0.15 weight percent Zr, from 0.00-0.10 weight percent Ti, from 0.10 weight percent maximum Si, from 0.12 weight percent maximum Fe, from 0.20 weight percent maximum Zn, and the balance Al and incidental impurities. The alloy should also be essentially Ag-free with Ag only being an accidental impurity in levels less than 0.05 weight percent maximum. In certain embodiments, the aluminum-copper-lithium alloys may be provided in the form of extruded products having improved combinations of strength and fracture toughness.

Abstract: A method of welding age-hardenable aluminum alloys to improve strength properties in the heat affected zone and the weld zone, the method comprising the steps of providing precipitation hardenable aluminum alloy members to be welded and subjecting said members to a first aging step for times and temperatures to generated strengthening precipitates. Thereafter, the aged members are welded to provide a welded assembly having a weld zone. The welded members are subjected to a second aging step to reprecipitate strengthening precipitates dissolved in the weld zone.

Abstract: Panel for aircraft landing strip.

Abstract: An aluminum alloy extrusion product having improved strength and fracture toughness, the aluminum base alloy comprised of 1.95 to 2.5 wt. % Cu, 1.9 to 2.5 wt. % Mg, 8.2 to 10 wt. % Zn, 0.05 to 0.25 wt. % Zr, max. 0.15 wt. % Si, max. 0.15 wt. % Fe, max. 0.1 wt. % Mn, the remainder aluminum and incidental elements and impurities.