Cold rolling is made from hot-rolled plates at room temperature. Although rolling will also heat up the steel plate during the processing, it is still called cold rolling. Since hot rolling undergoes continuous cold deformation, cold rolling has poor mechanical properties and too high hardness. It must be annealed to restore its mechanical properties. Those without annealing are called hard rolled coils. Hard rolled coils are generally used to make products that do not require bending or stretching.