Editing Iron (section)

===Thermite process===
{{Main|Thermite}}
Ignition of a mixture of aluminium powder and iron oxide yields metallic iron via the [[thermite reaction]]:

:{{chem2 | Fe2O3 + 2 Al -> 2 Fe + Al2O3 }}

Alternatively pig iron may be made into steel (with up to about 2% carbon) or wrought iron (commercially pure iron). Various processes have been used for this, including [[finery forge]]s, [[Puddling (metallurgy)|puddling]] furnaces, [[Bessemer converter]]s, [[open hearth furnace]]s, [[basic oxygen furnace]]s, and [[electric arc furnace]]s. In all cases, the objective is to oxidize some or all of the carbon, together with other impurities. On the other hand, other metals may be added to make alloy steels.{{sfn|Greenwood|Earnshaw|1997|p=1072}}<!-- why is this in production? The hardness of the steel depends upon its carbon content: the higher the percentage of carbon, the greater the hardness and the lesser the malleability. The properties of the steel can also be changed by several methods.-->