Cold-rolled Steel

Cold-rolled steel refers to steel produced through cold rolling. Cold rolling is the process of further rolling No.1 steel plate to the target thickness at room temperature. Compared with hot-rolled steel plates, cold-rolled steel plates are more precise in thickness, have a smooth and beautiful surface, and have various superior mechanical properties, especially in processing performance. Since the cold-rolled coil is relatively hard and brittle and not suitable for processing, cold-rolled steel plates usually require annealing, pickling, and surface leveling before being delivered to customers. The maximum thickness of cold rolling is below 0.1-8.0MM, and most factories have a thickness of 4.5MM or less. The minimum thickness and width are determined according to the equipment capabilities and market demands of each factory.

Processing method

Using hot-rolled steel coils as raw materials, cold continuous rolling is carried out after pickling to remove oxide scale, and the finished product is a hardened roll. Due to the cold work hardening caused by continuous cold deformation, the strength and hardness of the hardened roll increase, while the toughness and plasticity index decrease, so the stamping performance will deteriorate and can only be used for simple deformation parts. Hardened rolls can be used as raw materials for hot-dip galvanizing plants, as all hot-dip galvanizing units are equipped with annealing lines. The weight of the hardened roll is generally between 6-13.5 tons, and the steel coil is continuously rolled at room temperature for hot-rolled pickled coils.

Properties

Cold-rolled steel has high strength, but poor toughness and weldability, and is relatively hard and brittle with a bright surface.

Application

Cold-rolled steel coils are widely used in automobile manufacturing, electrical appliances, locomotives, aircraft, precision instruments, canned food, and many other applications. Cold-rolled steel plates are commonly referred to as cold-rolled carbon structural steel plates, also known as cold-rolled plates, generally referred to as cold plates, and sometimes mistakenly written as cold dishes. Cold plate is a hot-rolled steel plate of ordinary carbon structural steel, which is made into a thickness of less than 4 millimeters by further cold rolling. Since no oxidized iron plate is produced during room temperature rolling, the surface quality and dimensional accuracy of cold plates are good. With annealing treatment, the mechanical properties and process performance are better than hot-rolled steel plates. In many fields, especially in the household appliance manufacturing industry, cold plates have gradually replaced hot-rolled steel plates.