Method and composition for recycling aluminum containers

Abstract

The present disclosure provides improved processes and compositions for continuously casting aluminum alloys. The resulting aluminum alloy sheet is useful for container body stock.

1 - 27 . (canceled) 
     
     
         28 . A method, comprising:
 forming a melt composition comprising at least about 0.45 wt. % manganese, at least about 1.2 wt. % magnesium, at least about at least about 0.05 wt. % copper, at least about 0.2 wt. % iron, and at least about 0.1 wt. % silicon, wherein at least about 75% of the melt composition is derived from scrap, and wherein the balance of the melt composition consists essentially of aluminum and incidental additional materials and impurities;   adding aluminum prime to the melt composition to form a final melt composition, wherein the final melt composition comprises no more than about 25 wt. % prime aluminum; and   forming the final melt composition into an article.   
     
     
         29 . The method of  claim 28 , wherein at least about 80% of the melt composition is derived from scrap, wherein the scrap comprises used beverage containers, wherein the melt composition comprises at least about 0.50 wt. % manganese, at least about 1.25 wt. % magnesium, at least about at least about 0.10 wt. % copper, at least about 0.2 wt. % iron, and at least about 0.15 wt. % silicon, wherein the final melt composition comprises no more than about 20 wt. % prime aluminum, wherein the incidental additional materials and impurities is limited to about 0.05 wt. % but not more than each additional material and impurity but the sum total of all incidental materials and impurities does not exceed about 0.15 wt. % of the melt composition, and wherein the article comprises at least about 0.7 wt. % but no more than about 1.2 wt. % manganese, at least about 1.5 wt. % but no more than about 2 wt. % magnesium, at least about 0.2 wt. % but no more than about 0.6 wt. % copper, at least about 0.28 wt. % but no more than about 0.45 wt. % iron, and at least about 0.10 wt. % silicon. 
     
     
         30 . The method of  claim 29 , wherein at least about 85% of the melt composition is derived from scrap, wherein the scrap comprises used beverage containers, wherein the melt composition comprises at least about 0.50 wt. % but no more than about 1.1 wt. % manganese, at least about 1.3 wt. % but no more than about 2 wt. % magnesium, at least about at least about 0.15 wt. % but no more than about 0.5 wt. % copper, at least about 0.2 wt. % but no more than about 0.7 wt. % iron, and at least about 0.15 wt. % but no more than about 0.5 wt. % silicon, wherein the final melt composition comprises no more than about 15 wt. % prime aluminum, wherein the incidental additional materials and impurities is limited to about 0.03 wt. % but not more than each additional material and impurity but the sum total of all incidental materials and impurities does not exceed about 0.1 wt. % of the melt composition, and wherein the article comprises at least about 0.75 wt. % but no more than about 1.1 wt. % manganese, at least about 1.51 wt. % but no more than about 1.9 wt. % magnesium, at least about 0.25 wt. % but no more than about 0.5 wt. % copper, no more than about 0.45 wt. % iron, and at least about 0.15 wt. % silicon. 
     
     
         31 . The method of  claim 30 , wherein at least about 90% of the melt composition is derived from scrap, wherein the balance of the melt composition is derived from used beverage containers, wherein the melt composition comprises at least about 0.50 wt. % but no more than about 0.95 wt. % manganese, at least about 1.35 wt. % but no more than about 1.95 wt. % magnesium, at least about at least about 0.15 wt. % but no more than about 0.4 wt. % copper, at least about 0.2 wt. % but no more than about 0.67 wt. % iron, and at least about 0.15 wt. % but no more than about 0.45 wt. % silicon, wherein the final melt composition comprises no more than about 10 wt. % prime aluminum, wherein the incidental additional materials and impurities is limited to about 0.01 wt. % but not more than each additional material and impurity but the sum total of all incidental materials and impurities does not exceed about 0.1 wt. % of the melt composition, and wherein the article comprises at least about 0.8 wt. % but no more than about 1 wt. % manganese, at least about 1.52 wt. % but no more than about 1.8 wt. % magnesium, no more than about 0.4 wt. % copper, and no more than about 0.4 wt. % iron. 
     
     
         32 . The method of  claim 31 , wherein at least about 95% of the melt composition is derived from scrap, wherein the scrap comprises used beverage containers, wherein the melt composition comprises at least about 0.50 wt. % but no more than about 0.80 wt. % manganese, at least about 1.4 wt. % but no more than about 1.9 wt. % magnesium, at least about at least about 0.15 wt. % but no more than about 0.3 wt. % copper, and at least about 0.2 wt. % but no more than about 0.5 wt. % iron, wherein the final melt composition comprises no more than about 5 wt. % prime aluminum, wherein the sum total of all incidental materials and impurities does not exceed about 0.05 wt. % of the melt composition, and wherein the article comprises at least about 0.85 wt. % but no more than about 9 wt. % manganese, at least about 1.53 wt. % but no more than about 1.7 wt. % magnesium, and no more than about 0.35 wt. % copper. 
     
     
         33 . The method of  claim 32 , wherein the scrap comprises used beverage containers, wherein the melt composition comprises at least about 0.50 wt. % but no more than about 0.70 wt. % manganese and at least about 1.4 wt. % but no more than about 1.8 wt. % magnesium, wherein the article comprises at least about 1.54 wt. % but no more than about 1.65 wt. % magnesium, and wherein the forming step comprises:
 hot rolling the cast strip to form a hot rolled strip;   cold rolling the hot rolled strip to form a cold rolled strip; and   stabilize annealing the cold rolled strip at a minimum temperature of about 300 degrees Fahrenheit and a maximum temperature of about 500 degrees Fahrenheit to form the article.   
     
     
         34 . The method of  claim 33 , wherein the hot rolled strip is annealed at a minimum temperature of about 725 degrees Fahrenheit and a maximum temperature of about 900 degrees Fahrenheit, wherein the cold rolling step comprises a first cold rolling step to convert the hot rolled strip into a partially cold rolled strip and a second cold rolling step to convert the partially cold rolled strip into the cold rolled strip, and wherein the partially cold rolled strip is intermediate annealed at a minimum temperature of about 710 degrees Fahrenheit and a maximum temperature of about 850 degrees Fahrenheit. 
     
     
         35 . The method of  claim 28 , wherein the article is body stock for a beverage container. 
     
     
         36 . The method of  claim 28 , wherein the article is a component of a beverage container, the beverage container comprising a can end, can tab, and can body.