Aluminum strips and foils produced by hot rolling-cold rolling processes. Among them, aluminum profiles are mainly used in the construction and industrial fields, while aluminum sheets, strips and foils are mainly used in the fields of home appliances, food and beverages and batteries:
Continuous casting slabs or blooming slabs are used as raw materials. They are heated by a stepping heating furnace and dephosphorized by high-pressure water before entering the rough rolling mill. The rough rolled material is cut into head and tail and then enters the finishing mill for computer-controlled rolling. After final rolling, it undergoes laminar cooling (computer controlled cooling rate) and coiling by a coiler to become straight coils. The head and tail of straight hair rolls are often tongue-shaped and fish-tail-shaped, with poor thickness and width accuracy, and the edges often have defects such as wavy shapes, folded edges, and tower shapes. The coil weight is heavier and the inner diameter of the steel coil is 760mm. (Generally, the pipe making industry likes to use it.) After the straight hair roll is processed by head cutting, tail cutting, edge trimming and multi-pass straightening, flattening and other finishing lines, it is then cut into plates or re-rolled, which becomes: hot rolled Aluminum plates, flat hot-rolled aluminum coils, slit strips and other products. If the hot-rolled finished rolls are pickled to remove scale and oiled, they become hot-rolled pickled rolls.
Hot-rolled aluminum coils are used as raw materials, and the oxide scale is removed by pickling and then cold-rolled continuously. The finished product is hard-rolled coils. Due to the cold work hardening caused by continuous cold deformation, the strength and hardness of the hard-rolled coils increase, and the toughness and plasticity index decreases. , the stamping performance deteriorates and can only be used for parts with simple deformations. Hard rolled coils can be used as raw materials in hot-dip galvanizing plants because hot-dip galvanizing units are equipped with annealing lines. The weight of hard rolled coils is generally 6~13.5 tons, and the inner diameter of aluminum coils is 610mm. Generally, cold-rolled plates and coils should undergo continuous annealing (CAPL unit) or bell-type furnace de-annealing to eliminate cold work hardening and rolling stress, and achieve the mechanical performance indicators specified in the standard. The surface quality, appearance, and dimensional accuracy of cold-rolled aluminum sheets are better than those of hot-rolled sheets.
