ALUMINUM ALLOY EXTRUSIONS HAVING A SUBSTANTIALLY UNRECRYSTALLIZED STRUCTURE

摘要

A substantially unrecrystallized extrusion comprising about 3.6 to about 4.2 wt.% copper, about 1.0 to about 1.6 wt.% magnesium, about 0.3 to about 0.8 wt.% manganese, about 0.05 to about 0.25% zirconium, the balance substantially aluminum, incidental elements and impurities. The extrusion has a longitudinal yield strength of at least about 50 ksi and a longitudinal tensile ultimate strength of at least about 70 ksi. On a preferred basis, the extrusions of this invention include very low levels of both iron and silicon, typically on the order of less than 0.1 wt.% each, and more preferably about 0.05 wt.% or less iron and about 0.03 wt.% or less silicon.