Patent ID: 6764559
Filing Date: 2004-07-20
Classification: C22C,C22F,Y10T

Abstract:
In the production of an aluminum automotive frame member from a molten aluminum alloy using a continuous caster to cast the alloy into a slab, the method comprising:(a) providing a molten aluminum alloy consisting essentially of 2.7 to 3.6 wt. % Mg, 0.1 to 0.4 wt. % Mn, 0.02 to 0.2 wt. % Si, 0.05 to 0.30 wt. % Fe, 0.1 wt. % max. Cu, 0.1 wt. % max. Cr, 0.2 wt. % max. Zr, the remainder aluminum, incidental elements and impurities; (b) providing a continuous caster for continuously casting said molten aluminum alloy; (c) casting said molten aluminum alloy into a slab having Alâ€”Feâ€”Mn intermetallic particles; (d) rolling said slab into a sheet product; (e) annealing said sheet product to an O-temper condition, said sheet product having a substantial uniform distribution of said intermetallic particles; (f) forming said sheet in said O-temper condition into a tube having a seam; (g) welding said seam to provide a seam welded tube; (h) placing said seam welded tube in a forming die; and (i) hydroforming said seam welded tube to form said automotive frame member.