Improved mechanical properties through alloying
Pure aluminium consists of 99 to 99.8 percent aluminium. The higher the purity of aluminium, the better is its resistance to corrosion. However, pure aluminium does not excel in terms of mechanical properties; hence it is used in the form of alloys. The best mechanical properties are achieved by alloying aluminium with copper, nickel, magnesium and silicon.
Aluminium alloys for kneading (extruding, rolling, drawing and forging) are mostly based on magnesium and copper. Magnesium enhances mechanical strength (with proper treatment) and resistance to corrosion. However, along with that, it compromises the suitability for casting or forming and reduces electric conductivity. Copper significantly enhances mechanical strength, but compromises the resistance to corrosion. Aluminium alloys for casting are mostly based on the addition of silicon.
In the metal processing industry, aluminium production is second only to steel production. In recent years, the global production of aluminium has exceeded 30 million tons a year, which is more than the production volumes of copper, tin and lead combined.
Fields of application:
- alloys of the 5000 series are applied for decorative construction materials requiring anodising,
- alloys of the 6000 series are applied mostly for automotive industry products, since they are suitable for forming and hardening,
- alloys of the 7000 series are applied in aerospace and space technologies, since they are suitable for hardening.