Wear during aluminium foil jumbo roll rolling

Wear during aluminium foil jumbo roll rolling

During the rolling process of aluminium foil jumbo roll, due to the plastic deformation of the metal, new surfaces are continuously generated, and the contact surface has a high unit pressure, coupled with the characteristics of high deformation temperature and large sliding speed, so that the surface of the roll adheres. The phenomenon of metal and roll wear is particularly prominent. When the adhesion between the metal and the roll occurs, the sliding external friction between the two is transformed into the internal friction of the metal surface layer, and the shear deformation of the subsurface layer occurs, thereby changing the friction state at the part where the metal is adhered. This results in a change in the stress state of the metal and a change in the flow state. As a result, the friction increases, the energy consumption increases, the surface of the product is significantly damaged, the roll is rapidly worn, and the service life is shortened. In severe cases, the rolling process cannot be carried out normally.

The wear situation during rolling is extremely complex, and metal wear is related to factors such as metal material, surface oxide, work hardening, processing temperature, speed, lubricant, and surrounding environment. In the process of material deformation, the wear mechanism may be one or several mechanisms acting simultaneously. Moreover, the deformation process itself is also variable. During rolling, the roll is in contact with the rolling piece repeatedly and continuously, and the surface of the rolling piece entering the deformation zone is constantly changing. In addition, the surface of the workpiece is clean after pickling. When the workpiece is in contact with the dirty roll surface, the possibility of adhesion and the peeling of the worn particles are intensified due to plastic deformation and elongation. If the height of the worn particles is greater than the thickness of the oil film, then the particles It will be pressed against the surface to grind the surface of the roll.

The type of wear varies depending on the contact surface topography, contact conditions and environmental conditions. However, it can generally be divided into two types: mechanical wear and chemical wear. Mechanical wear is a type of wear process related to friction, abrasive wear, erosion, and fatigue; chemical wear is caused by the erosion of surfaces by various active substances, followed by friction and fragmentation of these reactants due to mechanical action. The different types of wear can occur individually, sequentially or simultaneously. The high stress on the wear surface is a common feature of various wear phenomena.