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Aluminum - Facts Behind the Metal

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					Aluminum - Facts Behind the Metal
A metallic element with symbol Al, aluminum is the 3rd most plentiful
element of Earth's crust, behind that of oxygen and silicon. The metal
has strong affinity towards oxygen and hence is not found in the
elemental form but in combined states, such as silicates or oxides.
Bauxite is the main mineral ore of aluminum, which is abundantly
available in tropical areas, such as - Africa, the West Indies, South
America and Australia. Bauxite contains all types of impurities - mainly
metals, such as iron - but comprises of 45 % to 60 % aluminum oxide, or
alumina.
In its metallic form, aluminum metal does not occur naturally. It occurs
only in combination with other minerals in the form of oxide or silicate
compounds that constitute about 8% of earth's crust.
According to estimates, about 29 million tons of aluminum is required to
meet the global demand every year. Of this total 29 million tons of total
aluminum, around 22 million tons is new aluminum and 7 million tons is
obtained by recycling the aluminum scrap. About 25% of the total amount
of aluminum used across the world is recycled material.
Fact - 50% of the aluminum cans used today in the US are recycled.
According to estimates since 1972 around 16 million tons of aluminum cans
have been recycled. These 785.6 billion aluminum cans if placed end-to-
end could stretch to the moon more than 249 times.
Production of Aluminum
Production of aluminum is a two stage process that comprises of various
intermediate steps. In the first stage, different mechanical and chemical
stages are used to purify the bauxite and recover the alumina with the
help of "Bayer Process".
Once the alumina - aluminum oxide trihydrate - is retrieved, it can be
electrolytically reduced (transformed through electrochemical means) into
metallic aluminum.
Some Facts -

Aluminum can be very strong, light (less than 1/3rd of the specific
gravity of copper, brass or steel), ductile, and malleable.
The metal is an excellent conductor of heat and electricity.
Polished aluminum has the highest reflectivity of any material - even
mirror glass.
The metal can be rolled, cast or extruded into an infinite array of
shapes.
As a packaging material, aluminum as unique barrier characteristics. It
resists corrosion and can be recycled again and again, without any loss
of quality or properties.
The metal can be mixed with small, often minute, quantities of other
materials, such as - copper, zinc, silicon, iron, magnesium, tin,
titanium, lithium, chromium, tungsten, manganese, nickel, and others to
create a variety of alloys with very different physical characteristics.
Aluminum metal is so widely used in todays' modern world that it is very
difficult to imaging a world without it. The amazing, unique properties
of this fundamental metal give it an extensive array of possible
applications, including - transport, packaging, electrical application,
medicine, and construction of homes and furniture.
For more articles related to metal casting and manufacturing technology,
log on to http://www.manufacturing-technology.blogspot.com A reliable
source of vast information on metal casting,
http://www.themetalcasting.com (Article written by Gary Emerson - A
graduate in mechanical and materials engineering with about 12 years
experience in manufacturing industry, including - tooling design, casting
methods, cast product design, machining initialization, and manufacturing
techniques. I've expertise in metal casting, including centrifugal
casting, die casting, permanent mold casting, sand casting, and
investment casting.

				
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posted:10/16/2010
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