Aluminums

Aluminums refers to aluminum metal and its commercial alloys. Aluminum is a chemical element with the symbol Al and atomic number 13. It is the third most abundant element in the Earth's crust, making up about 8.1% by weight. In pure form it is lightweight, soft, and highly ductile, but it is usually used in alloyed forms to improve strength and other properties.

Key properties of aluminums include a low density of about 2.7 g/cm3, good strength-to-weight ratio when alloyed, and strong resistance to corrosion due to a passive oxide film that forms on its surface. It also offers excellent thermal and electrical conductivity for a metal, good workability, and recyclability. Aluminum alloys commonly include magnesium, silicon, zinc, or copper, and many can be heat treated to adjust strength. Recycling aluminums is highly advantageous because it uses far less energy than primary production and typically retains properties.

Occurrence and production involve extracting the metal from its ore. The primary ore is bauxite. Alumina (Al2O3) is produced from bauxite via the Bayer process, and aluminum metal is produced by electrolysis in the Hall-Héroult process. Because smelting is energy-intensive, production is often concentrated near abundant electricity sources.

Applications of aluminums span packaging (such as beverage cans), transportation (aircraft, automobiles, trains), construction, electrical components, and a wide range of consumer products. The history of aluminums includes its isolation in the early 19th century and the development of efficient electrolysis in 1886, which enabled large-scale, affordable production.