Aluminium (Al)

A silvery-coloured, soft, light metal element with the symbol Al.

Aluminium is an abundant, soft, lightweight metal with appearance ranging from silvery to dull gray, depending on the surface roughness. It is non-toxic, non-magnetic, and non-sparking. Aluminium has about one-third the density and stiffness of steel. It is ductile and easily machined, cast, and extruded. Its corrosion resistance is excellent due to a thin surface layer of aluminium oxide that forms rapidly when the metal is exposed to air, effectively preventing further oxidation.

In 1886, American Charles Martin Hall patented an electrolytic process to extract aluminium, forming a company for its production which later became Alcoa. Americans adopted the name aluminium for most of the 19th century, as did Hall in all of his patents. However, in 1892, Hall used the aluminum spelling in an advertising handbill and the name was adopted in America owing to his domination of the aluminium business in that country.

Properties:

• Melting point 660°C
• Density 2.70 g/cm3 (Water = 1)

Identified in 1808 by Sir Humphrey Davy and named after alumina, the mineral from which he was trying to isolate it.