Aluminum Alloy Information

Aluminum alloy's come in many variations. An aluminum alloy is a metal that is composed of aluminum in concentrations of 85% or more and other elements such as iron, silicon, copper, magnesium, manganese and zinc. These elements are added to alter the physical properties of the metal such as strength. To make a proper alloy of Aluminum you must mix the other elements into molten Aluminum and it must be mixed thoroughly.

2xxx series alloys are alloys that combine copper and with the aluminum. The x's represents various numbers to differentiate the different alloys. Fore example 2024 is aircraft aluminum. These Aluminum-copper alloys have high strength and toughness but are more prone to atmospheric corrosion. These alloys when used are typically painted over.

The 6xxx series heat treatable, highly formable and weldable. Have moderately high strength but still retain their corrosion corrosion resistance. 6000 series alloys contain silicon and magnesium Example of uses for 6000 series Aluminum alloys is architecture. An example would be alloy 6061, which is the most widely used 6000 series aluminum alloy and is often used in truck frames.

The 7xxx series of alloys use Zinc as the primary alloy. Other elements such as magnesium may also be added but these additions are in quantities less than that of the Zinc. These alloys are very high strength alloy. Other elements such as copper and chromium may also be added in small quantities. These alloys are most widely used in aircraft.

The 2000, 6000 and 7000 groups of aluminum alloys are all heat treatable alloys. This means that they can be strengthened by heating followed by rapid cooling. Heat treating takes the solid, alloyed metal and heats it to a specific point. When in solution the elements mix freely. The rapid cooling, locks their distribution in place.

The 3000, 4000 and 5000 series of Aluminum alloys are not strengthened by the heat treating process. Instead, they are strengthend by cold working them. Cold working involves putting work into the metal to make it stronger. For example, rolling aluminum down to thinner gauges makes it stronger.

The 3xxx series of Aluminum alloys use Manganese as the major alloy element often with smaller amounts of magnesium added. Heat exchangers, cooking utensils and aluminum beverage cans are examples of 3000 series uses.

The 4xxx series alloys are Aluminum combined with silicon to lower the melting temperature. The 4xxx series is most often used for welding wire and brazing alloys.

Magnesium is the primary alloying agent in the 5xxx series and is one of the most widely used alloying elements for aluminum. Alloys in this series possess moderate to high strength characteristics, as well as good weldablility and resistance to corrosion in saltwater. Because of this, aluminum-magnesium alloys are widely used in building and construction, storage tanks, pressure vessels and marine applications.