Aluminum used on beverage cans is largely 3004 and 3104 aluminum alloy, which has been chosen based on light weight, resistance to corrosion, and excellent recyclability. In industrial statistics, cans made from aluminum have had more than 75% share in all types of beverage packaging due to inexpensive manufacturing and efficiency of recyclability, with nearly 69% of all cans produced globally using aluminum being recycled. The choice of which type of aluminum is used in beverage cans is based on a variety of primary factors, including strength, flexibility, and food safety.
Aluminum alloys like 3004 and 3104 contain about 1% manganese and 1% magnesium to improve malleability and strength while keeping light material. The typical 12-ounce aluminum can is under 14 grams, but will support up to 90 psi (pounds per square inch) internal pressure, or three times a car tire. Such durability is necessary for carbonated beverages where too much pressure otherwise would burst thinner materials.
Corrosion resistance is also a consideration in the selection of the right aluminum alloy. Aluminum cans must be resistant to exposure from acidic products like soft drinks, beer, and energy drinks with a pH ranging from 2.5 to 4.0. Unprotected aluminum would react with such acids and cause contamination and failure of structure. To avoid this, an epoxy or polymer coating is placed on the inside of the can to ensure that the metal does not contaminate the taste of the drink or deteriorate with time.
Recyclability contributes significantly to the popularity of aluminum for use in beverage packaging. Unlike plastics, aluminum retains 100% of its original characteristics when it is melted down and reprocessed. The recycling of aluminum is 95% less energy intensive than producing new aluminum from bauxite ore, reducing significantly carbon emissions and its impact on the environment. Indeed, an Aluminum Association suggests that a used beverage can will be recycled and back on the store shelf within 60 days, making one of the most environmentally friendly packaging products in the world.
The beginning of the aluminum can was in 1959, when the first all-aluminum beer can was made by Coors Beer Company. Since then, advances in manufacturing technology and materials science have led to lighter, stronger, and more efficient can designs. The wall thickness of the modern aluminum can is as little as 0.097 mm, thinner than a human hair, but yet strong enough to hold pressurized fluids.
Entrepreneur and environmental activist Elon Musk has stated, “Sustainability is not just about energy; it’s about materials too.” The beverage industry’s use of aluminum fits into this thinking, offering a durable, economical, and eco-friendly solution. Choosing what type of aluminum is used in beverage cans is essential to obtaining performance, cost, and environmental responsibility, and that is why aluminum is the material of choice for beverage packaging worldwide.