Patent ID: 6290785
Filing Date: 2001-09-18
Classification: C22C,C22F

Abstract:
Aluminum alloy sheet produced by a method, comprising:(a) continuously casting an aluminum alloy melt to form a cast strip;(b) heating the cast strip to a temperature ranging from about 820 to about 1,080.degree. F. to induce recrystallization of the cast strip and form a heated cast strip;(c) hot rolling the heated cast strip to form a hot rolled strip;(d) cold rolling the hot rolled strip to form an intermediate cold rolled strip; and(e) continuously annealing the intermediate cold rolled strip in an induction heater to form aluminum alloy sheet, wherein the aluminum alloy sheet has a substantially equiaxed grain structure and a substantially uniform, fine-grain size throughout the volume of the sheet, wherein the sheet includes the following:(i) from about 0.10 to about 0.20 wt % manganese;(ii) from about 3.5 to about 4.9 wt % magnesium;(iii) from about 0.05 to about 0.10 wt % copper;(iv) from about 0.10 to about 0.20 wt % iron; and(v) from about 0.05 to about 0.10 wt % silicon, with the remainder being aluminum and incidental additional materials and impurities.