The belt rolling method is currently the main method of aluminum foil production. This method uses hot-rolled plates or melt continuous casting and rolling plates as aluminum foil materials. Its main features are high production efficiency (rolling speed up to 2500 m/min), good surface quality and uniform thickness. Generally, two or more layers are used in the final rolling pass. The thinnest aluminum foil produced by this method can reach 0.005 mm and the width can reach 2000 mm.
The traditional process of using hot rolling to produce foil is: semi-continuous casting is used to cast aluminum melt into slabs, which are hot-rolled and cold-rolled to make 0.4-1mm thick plates as aluminum foil wool. After the foil wool is annealed at a temperature higher than the recrystallization temperature, it is placed on a foil rolling mill for several passes of cold rolling to produce an aluminum foil product. Compared with hot-rolled billets, the quality of cast-rolled billets is more difficult to control.
