Aluminum-Widely used metal after steel.
Aluminum is the world’s most abundant metal and is the third most common element comprising 8% of the earth’s crust. The versatility of aluminum makes it the most widely used metal after steel. Aluminum is derived from the mineral bauxite. Bauxite is converted to aluminum oxide (alumina) via the Bayer Process. The alumina is then converted to aluminum metal using electrolytic cells and the Hall-Heroult Process.
Worldwide demand for aluminum is around 29 million tons per year. About 22 million tons is new aluminum and 7 million tons is recycled aluminum scrap. The use of recycled aluminum is economically and environmentally compelling. It takes 14,000 kWh to produce 1 tonne of new aluminum. Conversely it takes only 5% of this to remelt and recycle one tonne of aluminum. There is no difference in quality between virgin and recycled aluminum alloys.
Pure aluminum is soft, ductile, corrosion resistant and has a high electrical conductivity. It is widely used for foil and conductor cables, but alloying with other elements is necessary to provide the higher strengths needed for other applications. Aluminum is one of the lightest engineering metals, having a strength to weight ratio superior to steel.
By utilizing various combinations of its advantageous properties such as strength, lightness, corrosion resistance, recyclability and formability, aluminium is being employed in an ever-increasing number of applications. This array of products ranges from structural materials through to thin packaging foils.