Cold Rolling Mill

Cold rolling is a work hardening process that changes the structure of metals and is often used to process metals such as steel. Read on to learn more about what a cold rolling mill is, how it is produced, and what it is used for.

In simple terms, cold rolling is the process of strengthening steel by changing its shape without heating. Cold rolling, unlike hot rolling (such as hot rolled steel), can only be performed when the metal is below its recrystallization temperature. Hot rolling at high temperature and cold rolling at room temperature. Instead of heat, mechanical stress is used to change the structure of a metal. Strain hardening can increase the strength of the metal by 20% and also improve the surface finish of the metal.

During the cold rolling process, when the metal is subjected to mechanical stress, the crystal structure of the metal will be permanently changed. This gives it increased strength and often improved corrosion resistance. In addition to improved surface finish, another advantage of cold rolling is higher dimensional accuracy.

The cold mill can be precisely manufactured, allowing the metal to be produced to extremely tight tolerances. Work hardening of metal materials by cold rolling allows us to achieve various degrees of tempering, such as quarter hardness, half hardness and full hardness. The level of hardness depends on how much cold working has been done to the steel. Quarter, half, and full hard stocks have even larger reductions (sometimes up to 50%). This increases the yield point but decreases the ductility of the steel. Quarter-hard steel can be bent without breaking, semi-hard steel can be bent 90 degrees, and all-hard steel can be bent 45 degrees without breaking. Cold-rolled metal is often used in applications where the metal needs to be bent without the risk of breaking.