Aluminum metal was first isolated in 1825 by the Danish physicist and chemist Hans Christian Oersted, but an economic method of commercial production was discovered only in 1886 by Charles M. Hall of the US and Paul-Louis Toussaint Héroult of France. Both men were working independently at the time of their discoveries. The world aluminum industry is still based on the Hall-Héroult method of production. Because this process requires large amounts of electricity, smelters are located in those areas, such as Canada, where there is an abundance of electricity at a reasonable cost.
Combining aluminum with other metals to produce alloys enhances its characteristics and increases its versatility. The most common metals used in combination with aluminum are COPPER, magnesium, manganese, silicon and ZINC. Aluminum's tensile strength, hardness, corrosion resistance and heat-treatment properties improve when alloyed with one or more of these metals. Some copper-aluminum alloys, for example, can exceed the tensile strength of mild steel by as much as 50%.
Bauxite, the main ore of aluminum, contains about 50-60% alumina (aluminum oxide, Al2O3) and is formed by the weathering of aluminum-rich rocks under tropical conditions. Aluminum is produced by separating pure alumina from bauxite in a refinery, then treating the alumina by electrolysis. An electric current flowing through a molten electrolyte, in which alumina has been dissolved, separates the aluminum oxide into oxygen, which collects on carbon anodes immersed in the electrolyte, and aluminum metal, which collects on the bottom of the carbon-lined cell (cathode). On average, it takes about 4 t of bauxite to obtain 2 t of aluminum oxide, which in turn yield 1 t of metal. The word "aluminum" was suggested by Sir Humphry Davy in the early 1800s. It has been retained in North America, but has been modified to "aluminium" in the rest of the world.
In both its pure and alloyed forms, aluminum is used to make a variety of products for the consumer and capital-goods markets. The largest markets for aluminum are transportation, packaging, building and construction, electrical, machinery and equipment, and consumer goods. North America is the largest consuming region, followed by Asia and Europe.