Disclosed is an Al--Cu alloy of the AA2000-series alloys with high
toughness and an improved strength, including the following composition
(in weight percent) Cu 4.5-5.5, Mg 0.5-1.6, Mn.ltoreq.0.80,
Zr.ltoreq.0.18, Cr.ltoreq.0.18, Si.ltoreq.0.15, Fe.ltoreq.0.15, the
balance essentially aluminum and incidental elements and impurities, and
wherein the amount (in weight %) of magnesium is either: (a) in a range
of 1.0 to 1.6%, or alternatively (b) in a range of 0.50 to 1.2% when the
amount of dispersoid forming elements such as Cr, Zr or Mn is controlled
and (in weight %) in a range of 0.10 to 0.70%.