Aluminum foil can be divided into industrial aluminum foil and packaging aluminum foil. The chemical composition of industrial aluminum foil is relatively pure, and the thickness is 0.005-0.2mm. It is mainly used as capacitor, heat insulation material and moisture proof material in electrical and electronic industry. The thickness of packaging aluminum foil is generally 0.007 ~ 0.1mm, including flat foil, printing foil, colored printing foil and paper mounted aluminum foil, which are mainly used as packaging materials for food, tea, paper cigarette, etc.

Aluminum foil rolling is seamless rolling, and the roll is always in elastic flattening state. During rolling, the thickness of foil is controlled by adjusting rolling force, rolling speed and controlling tension. In rough rolling, the thickness of foil is controlled by rolling force; in finishing rolling, the thickness of foil decreases with the increase of rolling speed; the greater the tension, the smaller the thickness; in order to prevent fragment, the tension is usually 0.2-0.4 of the conditional yield strength σ 0.2 of the foil. The rolling thickness of aluminum foil is often adjusted by adding "thick oil" or "thin oil" into lubricating oil during low speed rolling. Lubricant and roll condition have important influence on foil quality. The aluminum foil blank is from cold rolled aluminum coil, which is generally pre annealed at 340-480 ℃ with a thickness of 0.4-0.7mm. During rolling, the pass deformation rate is about 50%, and the total deformation rate can reach more than 95%. Foil with thickness less than 0.01-0.02 mm should be rolled and double folded