Cold-rolled sheet is produced by rolling hot-rolled coils at room temperature below the recrystallization temperature. Since it is rolled at room temperature without generating iron oxide scale, the surface quality of the cold sheet is excellent, and the dimensional accuracy is high. In addition, through annealing treatment, its mechanical properties and process performance are superior to those of hot-rolled thin sheets. It has gradually replaced hot-rolled thin sheets in many fields, especially in the fields of home appliance manufacturing, security door panels, filing cabinets, enamel materials, barrel materials, writing boards, stamping parts, automotive manufacturing, electrical products, etc. Cold-rolled products can be produced in the form of continuous annealing (CA) or intermittent annealing (BA).