Patent ID: 6991689

Claim:
A method of producing an aluminum based alloy sheet or plate product, wherein the sheet or plate product is produced directly by a standard procedure consisting of the steps of: a) forging and/or hot rolling to be the desired thickness; b) solution heat treatment; c) quenching; d) optional stretching; and, e) age hardening to the desired temper, wherein the alloy consists essentially of a composition within the following ranges, all of the ranges being specified in weight percent: lithium 2.0 to 2.8; magnesium 0.4 to less than 1.0; copper 2.4 to 3.0; manganese 0.1 to 1.2; zirconium up to 0.2; grain controlling elements up to 2.0; and aluminum balance, and further, wherein the sheet or plate product contains homogeneous distributions of sub-micron scale Al—Cu—Mn intermetallic phases in the sheet product that improve strength and hardness.