Aluminum cans are the most commonly used beverage packaging materials in life. The aluminum for cans is mainly composed of three kinds of aluminum alloys with different compositions: 3004 aluminum for can body, 5052 aluminium coil for caps and 5182 aluminum for pull ring. Aluminum alloy is the key to making the can, the shape is not formed and the pull of the can lid can not open are all because of the aluminum alloy. Thus, the right aluminum alloy should be usedi n the right places of aluminum cans.
The can body for aluminum cans is mainly made of 3004 aluminum alloy coil, and the 3004 aluminum coil is a variant alloy of 3003. It has good formability, weldability, corrosion resistance and solderability. Since aluminum itself has good oxidation resistance, it is well used in cans to prevent oxidation and corrosion of carbonated beverages on the can.
The caps for the aluminum cans is made of 5052 aluminium coil, and the ring for the pull ring is made of alloy 5182. Both 5052 alloy and 5182 alloy belong to the aluminum-magnesium alloy, which have good corrosion resistance, good weldability, cold workability, medium strength, and the surface is very bright after polishing. However, the 5182 alloy is relatively high in magnesium content compared to the 5052 aluminum alloy sheet, and a small amount of silicon is added, so the weldability is better than that of the 5052 alloy. Therefore, the 5052 alloy is mostly used for the can lid, and the 5182 alloy is mostly used for the pull ring.