It is manufactured from hot rolled coil that has been
chemically cleaned before being rolled. The coil is initially cold, however while being reduced, the coil will
get hotter as the steel work hardens.
The cold rolling reduces the thickness of the steel and at the same time changes the mechanical properties of
the steel. Cold rolled steel must be further processed, as the steel will react with water in the air and
form rust. In most cases, it is covered with a thin layer of oil to prevent oxygen reacting with surface.
The steel coils can be annealed (heated in a controlled atmosphere) to make the steel more formable
(cold rolled annealed) or further processed on the metallic coating line, with a coating of either zinc
(galvanised) or zinc-aluminium alloy (ZINCALUME¢ç steel) applied. Cold rolled steel is available in a range
of grades, each with a range of properties for differing applications.
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