Aluminium is called the green metal because it is a very environmentally friendly metal. Recycling this material saves 95% of the energy required to produce aluminium from raw materials. This means it plays a key role in human ecology.
Around 8% of the earth's crust is reported to contain aluminium in the form of different minerals. This results in different kinds of metals of which have limited availability of aluminium in their raw forms.
We have outlined the key properties of aluminium which make it a highly useful material for construction here:
The density of aluminium is approx. 2.6 to 2.8 g per cm³. This is approx. one third of the density of steel, which is why aluminium is also called a light metal. It has a low density because of a lower atomic weight compared to wither metals.
Aluminum can become one of the toughest metals on earth. Aluminum alloys are used in many applications where strength and durability are needed. High strength aluminium can be seen in the engineering of planes and vehicles and even some of the world's tallest skyscrapers. Aluminium's strength is fortified by adding elements such as silicon, magnesium and lithium to the pure metal. This process can result in a metal as strong if not stronger than steel.
Due to aluminum's highly malleable (second in the world after gold) properties it can be rolled or hammered into extremely thin sheets without breaking. This makes it a suitable metal for a large range of product designs such as window frames and consumer packaging.
Aluminium corrosion resistance is very good in most environments when untreated. This is primarily because aluminium spontaneously forms a thin but effective oxide layer that prevents further oxidation. Aluminium oxide is impermeable and, unlike the oxide layers on many other metals, it adheres strongly to the parent metal. If damaged mechanically, aluminium’s oxide layer repairs itself immediately.This oxide layer is one of the main reasons for aluminium’s good corrosion properties.
Conductivity in Aluminum. Pure aluminum has a thermal conductivity of about 235 watts per kelvin per meter, and an electrical conductivity (at room temperature) of about 38 million siemens per meter. Aluminum alloys can have much a lower conductivity, but rarely as low as iron or steel.
According to British Standard BS 476, aluminium is described as non-combustible. Therefore when aluminium is exposed to a prolonged fire environment it will begin to melt (not burn), provided that the metal's temperature passes the melting point.
Aluminium can be recycled forever: It can be melted down and reformed without losing any quality, and the process can be repeated over and over again. Recycling 1 tonne of aluminium saves 9 tonnes of CO2 emissions and the process is quick; an aluminium can you throw in the bin can be back on the shelf in 6 weeks
Aluminium is durable due to its long lifespan. Aluminium is especially durable in end-use. In this way aluminium lasts for decades and the cut off value of aluminium's lifespan in the construction sector is 60 years. The required energy in combination with the long life span is what makes aluminium durable.
when aluminium metal was brand new, it used to be more precious than gold. Now aluminium is the most abundant metal on Earth but it is still expensive. This is largely because of the amount of electricity used in the extraction process. Aluminium ore is called bauxite (Al 2O 3) which is purified to yield a white powder called aluminium oxide (also known as alumina). From this aluminium can be extracted. However, due to the many beneficial properties of aluminium the price of aluminium can be seen as affordable compared to other metals for for production.