The cold-rolled steel sheet is a steel sheet obtained by further thinning the steel sheet to a target thickness below the recrystallization temperature under room temperature conditions. Compared with hot rolled steel, the thickness of cold rolled steel is more accurate, and the surface is smooth and beautiful. Cold-rolled steel sheets are processed from hot-rolled sheets at room temperature, although the temperature of the steel sheets will be heated up during the processing. The thickness of the cold-rolled sheet is generally between 0.1 and 8.0 mm. The thickness of the cold-rolled sheet produced by most factories is below 4.5 mm. The thickness and width of the cold-rolled sheet are determined according to the equipment capacity and market demand of each factory.
Cold-rolled steel sheets generally do not have a heating process before rolling. However, due to the small thickness of the strip, it is easy to have problems with the shape of the strip. Moreover, the cold-rolled steel sheet is a finished product. Therefore, in order to control the dimensional accuracy and surface quality of the steel strip, many complicated processes are used. The production line of cold-rolled steel plate is long, the equipment is many, and the process is complicated. With the improvement of users' requirements for strip dimensional accuracy, shape and surface quality, the control model, l1 and l2 systems, and shape control methods of cold rolling steel mills are more than those of hot rolling. Moreover, the temperature of the roll and the strip is also one of the more important control indicators. By definition, the ingot or billet is difficult to deform at room temperature and difficult to process. Most of the steel is rolled by hot rolling. However, because iron oxide scale is easily formed on the surface of the steel at high temperature, the surface of the hot-rolled steel is rough and the size fluctuates greatly. Therefore, it is required that the surface is smooth, the size is accurate, and the steel with good mechanical properties is produced by using the hot-rolled semi-finished product or finished product as the raw material and then using the cold-rolled steel plate method.
Cold-rolled steel strips are widely used, such as automobile manufacturing, electrical products, rolling stock, aviation, precision instruments, and canned food. Cold-rolled steel sheet is a hot-rolled steel strip of ordinary carbon structural steel, which is further cold-rolled to make a steel sheet with a thickness of less than 4mm. Due to rolling at room temperature, no iron oxide scale is produced. Therefore, the cold plate has good surface quality and high dimensional accuracy. Coupled with annealing treatment, its mechanical properties and process properties are better than those of hot-rolled steel sheets. In many fields, especially In the field of home appliance manufacturing, it has gradually replaced hot-rolled sheet steel.