Classification of aluminum alloys

Aluminium alloys are divided into:

1 series: features: containing more than 99.00% aluminum, good conductivity, good corrosion resistance, good weldability, low strength, can not be strengthened by heat treatment. Application: high purity aluminum (more than 99.9% aluminum) is mainly used in scientific experiments. Chemical industry and special uses.

2 series: features: aluminum alloy with copper as the main alloy element. Manganese, magnesium, lead and bismuth are also added for machinability. Such as: 2011 alloy, during melting process should pay attention to the safety protection (can produce harmful gases). 2014 alloy used in aerospace industry, high strength. The strength of 2017 alloy is lower than that of 2014 alloy, but it is easier to be machined. 2014 can be strengthened by heat treatment. Disadvantages: the tendency of intergranular corrosion is serious. Range of application: aerospace industry(2014 alloy), screw bead(2011 alloy) and the use of higher temperatures of the industry(2017 alloy).

3 series: features: manganese as the main alloy element of aluminum alloy, not heat treatment strengthening, corrosion resistance, good weldability,good plasticity.(close to super aluminum alloy). Disadvantages: low strength, but can be hardened by cold working to strengthen the strength. It is easy to produce coarse grains during annealing. Application scope: oil guide seamless tube used in aircraft(3003 alloy), ring-pull cans(3004 alloy).

4 series: mainly silicon, not commonly used. Some of the 4 series alloys can be strengthened by heat treatment, but some of the 4 series alloys can not be heat-treated.

5 series: features: magnesium is the main alloy element. Good weldability, good fatigue strength, can not be strengthened by heat treatment, only cold working to improve the strength. Application: handle of lawn mower, duct of aircraft fuel tank, bulletproof vest.

6 series: features: mainly magnesium and silicon. Mg₂Si is the main strengthening phase, which is the most widely used alloy at present. Most of them are used in 6063 and 6061, the others are 6082, 6160, 6125, 6262, 6060, 6005, 6463. The intensities of 6063, 6060 and 6463 are lower in 6 series. The intensities of 6262, 6005, 6082 and 6061 are higher in 6 series. Characteristics: medium strength, good corrosion resistance, good welding performance, good technological performance (easy to extrude out of shape),oxidation coloring performance. Application: energy tools (eg: car luggage rack, door, window, car body, heat sink, compartment housing).

7 series: features: mainly zinc, but sometimes to add a small amount of magnesium, copper. Superhard aluminum alloys contain zinc, lead, magnesium and copper alloys close to the hardness of steel. The extrusion speed is slower than that of 6 series alloy, and the welding performance is better. 7005 and 7075 are the highest grades in the 7 series, which can be strengthened by heat treatment. Applications: aviation (aircraft bearing components, landing gear), rockets, propellers, spacecraft.