Hot rolling

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The metallurgical process of Hot rolling, used mainly to produce sheet metal or simple cross sections from billets describes the method of when industrial metal is passed or deformed between a set of work rolls and the temperature of the metal is generally above its recrystallization temperature, as opposed to cold rolling, which takes place below this temperature. This permits large deformations of the metal to be achieved with a low number of rolling cycles.

Because the metal is worked before crystal structures have formed, this process does not itself affect its microstructural properties. Hot rolling is primarily concerned with manipulating material shape and geometry rather than mechanical properties. This is achieved by heating a component or material to its upper critical temperature and then applying controlled load which forms the material to a desired specification or size.

Mechanical properties of the material in its final as-rolled form is a function of: the material chemistry, reheat temperature, rate of temperature decrease during deformation, rate of deformation, heat of deformation, total reduction, recovery time, recrystallisation time, and subsequent rate of cooling after deformation.