Properties of aluminium
In the solar mounting system, we need the structure to be solid to support the whole solar PV system, and last decades in severe weather conditions, outdoor environment where there is rain, sometimes salty, chemical.
Aluminium offers a rare combination of valuable properties. It is one of the lightest metals in the world: it’s almost three times lighter than iron but it’s also very strong, extremely flexible and corrosion resistant because its surface is always covered in an extremely thin and yet very strong layer of oxide film. It doesn’t magnetise, it’s a great electricity conductor and forms alloys with practically all other metals.
Aluminium can be easily processed using pressure both when it’s hot and when it’s cold. It can be rolled, pulled and stamped. Aluminium doesn’t catch fire, it doesn’t need special paint and unlike plastics it’s not toxic. It’s also very pliable so sheets just 4 microns thick can be made from it, as well as extra thin wire. The extra-thin foil that can be made from aluminium is three times thinner than a human hair. In addition, aluminium is more cost effective than other metals and materials.
Since aluminium easily forms compounds with other chemical elements, a huge variety of aluminium alloys have been developed. Even a very small amount of admixtures can drastically change the properties of the metal, making it possible to use it in new areas. For example, in ordinary life you can find aluminium mixed with silicon and magnesium literally on the road, i.e. in the aluminium alloy wheels, in the engines, chassis and other parts of modern automobiles. As for aluminium zinc alloy, chances are you might be holding it in your hands right now as it’s this alloy that’s widely used in the production of mobile phones and tablet PCs. In the meantime, scientists keep developing new aluminium alloys.
The modern construction, automotive, aviation, energy, food and other industries would be impossible without aluminium. In addition, aluminium has become a symbol of progress: all cutting edge devices and vehicles are made from aluminium. (link to the Uses section)
It would seem that the mix of qualities enumerated above would already be enough to make aluminium the top choice in industry, however, there is another property that is just as significant: aluminium can be reused over and over again. Both aluminium and its alloys can be melted down and reused without any detriment to its mechanical properties. Scientists have estimated that 1 kg of recycled aluminium cans can save up to 8 kg of bauxite, 4 kg of various fluorides and up to 15 KWH of electricity.
About 75% of aluminium produced in the time that the aluminium industry has existed is still in use today.