ALUMINUM ALLOYS FOR HIGHLY SHAPED PACKAGING PRODUCTS AND METHODS OF MAKING THE SAME
The disclosure is related to new, formable and strong aluminum alloys for making packaging products such as bottles and cans.
1 . A method of making an aluminum alloy sheet comprising the sequential steps of:
(i) direct chill (DC) casting, wherein the casting comprises a casting speed of 50 to 300 mm/min;
(ii) homogenizing, wherein the homogenizing comprises heating to 550° C. to 650° C. at a rate of 30-60° C./hr, soaking for 1-6 hours, cooling to 450° C. to 500° C., and soaking for 8-18 hours;
(iii) hot rolling, wherein the hot rolling comprises break-down rolling and hot rolling to a gauge of about 1.5 mm to about 3 mm; and
(iv) cold rolling to form a cold rolled sheet.
2 . The method of claim 1 , further comprising batch annealing.
3 . The method of claim 1 , wherein the cold rolling comprises cold rolling to a final gauge bottle stock.
4 . The method of claim 1 , further comprising the steps of:
(v) flash annealing, wherein the flash annealing comprises heating the cold rolled sheet to between about 400° C. and 560° C. at a rate between 100° C./sec and 300° C./sec, and quenching at a rate between 100° C./sec and 300° C./sec; and
(vi) finish cold rolling to form a sheet.