Carbonyl metallurgy is used to manufacture products of

iron Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...

, nickel,

steel Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...

, and other

metal A metal () is a material that, when polished or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. These properties are all associated wit ...

s. Coatings are produced by vapor plating using metal carbonyl vapors. These are metal-

ligand In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's el ...

complexes where

carbon monoxide Carbon monoxide (chemical formula CO) is a poisonous, flammable gas that is colorless, odorless, tasteless, and slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...

is bonded to individual atoms of metals . Iron carbonyl is stable as iron pentacarbonyl, where five carbon monoxide molecules are pendently bonded to the iron atom, while nickel carbonyl is stable as nickel tetracarbonyl, which has four carbon monoxide molecules pendantly bonded to the nickel atom. Both can be formed by the exposure of the powdered metal to carbon monoxide gas at temperatures of around 75 degrees Celsius. Both the metal carbonyls decompose near 175 °C, resulting in a vapor plated metallic coating. The thickness of the vapor plated deposit can be increased to desired thicknesses by controlling the amount of metal carbonyl used and the duration of the plating process. Vale Inco produces over 100 million pounds (''ca''. 45000

tonnes The tonne ( or ; symbol: t) is a unit of mass equal to 1,000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton in the United States to distinguish it from the non-metric units of the s ...

) of nickel metal annually by the carbonyl process. The carbonyl process has been used to produce molds in custom shapes for industry. Such molds have been used in plastic molding and other manufacturing techniques. William Jenkin developed many of the techniques and procedures used in carbonyl metallurgy. Carbonyl metallurgy is useful as a low-temperature metal coating technique that may find many applications in the future. File:Nickel-tetracarbonyl-2D.png, Nickel tetracarbonyl File:Fe(CO)5.svg, Iron pentacarbonyl

* Iron recovery and steel manufacture using carbonyl chemistry - http://www.space-mining.com/IRONRECOVERY.htm (archived: https://web.archive.org/web/20120210151936/http://www.space-mining.com/IRONRECOVERY.htm) * Beneficiation of asteroidal iron by carbonyl metallurgy - http://www.space-mining.com/beneficiation.html (archived: https://web.archive.org/web/20120210152024/http://www.space-mining.com/beneficiation.html) * William Jenkin inventor of numerous carbonyl processes - https://web.archive.org/web/20080511182043/http://www.wcjenkin.com/ * Preparation of Iron Carbonyl

* Preparation of metallic shaped bodies - http://www.patentstorm.us/patents/5802437-claims.html{{dead link, date=November 2016 , bot=InternetArchiveBot , fix-attempted=yes Chemical processes Coatings Metallurgy

See also

Further reading