The particularity of aluminum foil rolling
In the production of double foil, the rolling of aluminum foil is divided into three processes: coarse rolling, medium rolling and fine rolling, and from the point of view of technology, it can be divided roughly from the thickness of rolling outlet, The general division is that the outlet thickness is greater than or equal to 0.05mm for coarse rolling, the outlet thickness is medium rolling between 0.013~0.05, the outlet thickness is less than 0.013mm of single finished products and double rolling finished products for fine rolling.
The rolling characteristics of coarse rolling and aluminum strip are similar, the thickness control mainly depends on rolling force and post-tension, the thickness of rough rolling processing rate is very small, its rolling characteristics have been completely different from the rolling of aluminum plate strip, with the particularity of aluminum foil rolling, its characteristics are mainly as follows: (1) aluminum strip rolling. In order to make aluminum strip thinning mainly rely on rolling force, so the automatic control mode of plate thickness is to the constant roller seam as the main control mode of AGC, even if the rolling force changes, at any time to adjust the roller seam so that the roller seam to maintain a certain value can also obtain a uniform thickness of the plate strip. and aluminum foil rolling to medium finishing rolling, because the thickness of aluminum foil is extremely thin, rolling, increase the rolling force, so that the roll to produce elastic deformation than the rolling material to produce plastic deformation is easier, the roll of elastic flattening can not be ignored, roll of the rolling flattening determines the aluminum foil rolling, rolling force has not been like the role of rolling plate,
Aluminum foil rolling is generally under constant pressure without roller seam rolling, adjust the thickness of aluminum foil mainly rely on adjusting the tension and rolling speed. (2) stacked rolling. For extremely thin aluminum foil with a thickness of less than 0.012mm (the thickness size is related to the diameter of the working roller), because of the elastic flattening of the roll, it is very difficult to use a single rolling method, so the double-joint rolling method, that is, the two aluminum foil in the middle of the lubricant, and then combined to roll the method
Stacking rolling can not only roll out the very thin aluminum foil that cannot be produced by single rolling, but also reduce the number of break bands and improve labor productivity, and the single-sided optical aluminum foil of 0.006mm~0.03mm can be produced by using this process. (3) Speed effect. In the process of aluminum foil rolling, the phenomenon that the thickness of foil becomes thinner with the rise of the rolling system is called the velocity effect.
The interpretation of the velocity effect mechanism has yet to be studied in depth, and the reasons for the speed effect are generally considered to have the following three aspects: 1), the friction state between the working roller and the rolling material changes, with the increase of the rolling speed, the intake of lubricating oil increases, so that the lubrication state between the roll and the rolling material changes.
The friction coefficient decreases, the oil film thickens, and the thickness of the aluminum foil decreases thinner. 2), the change of the mill itself.
With the increase of rolling speed, the roller neck will float in the bearing, so that two of the rollers loaded by the interaction will move in the direction of mutual tightening. 3), the material is rolled and deformed when the processing softening. The rolling speed of high speed aluminum foil mill is very high, with the increase of rolling speed, the temperature of rolling deformation zone is high, and the metal temperature in the calculated deformation area can rise to 200 ℃, which is equivalent to one intermediate recovery annealing, which causes the process softening phenomenon of rolling material.
Formulate the principle of aluminum foil rolling process
The total processing rate of the total processing rate of ① refers to the total deformation degree of the foil after recrystallization annealing to rolling out the finished product.
Generally speaking, the total processing rate of 1 series can reach more than 99%, some 8 series of products can also reach this value, but the total processing rate of aluminum alloy foil is generally less than 90%.
② the determination of the processing rate of the road secondary processing rate is the core of the rolling process, pure aluminum series products, its road processing rate can reach 65%, billet annealing after the first time, it is not appropriate to use too large processing rate, generally take about 50%.
The thickness measurement method of aluminum foil rolling mainly has eddy current measurement thickness, isotope ray thickness measurement and X-ray measurement thickness. X-ray thickness measurement is one of the most common thickness measurement methods used in aluminum foil production, especially in high-speed aluminum foil mill. Thickness control method for aluminum foil rolling: rolling force control, tension control, rolling speed control, tension/speed, speed/tension control.