Influence of edge thermal spraying on the temperature field and thermal crown of work roll during cold rolling of aluminum alloy strip

As a mature shape-controlling technology, the segmented cooling of the work roll can directly change the thermal expansion of the work roll, and that affects the thickness and elongation distribution along the width direction of the strip. However, it cannot improve shape defects at the two edges of a strip. In this paper, edge thermal spraying is applied to solve the shape defects at the two edges of a strip because it can change the temperature field and thermal expansion locally at the two edges of the work roll, which is contrary to cooling. Through establishing and solving the thermodynamic coupling finite element model of the work roll, it was found that edge thermal spraying can raise the temperature and thermal expansion at the edges of the work roll and hardly influence the temperature inside the work roll. The relationship between the local increment of thermal expansion and the temperature difference between cooling water and heating water was fitted to a linear model. Then, this model was applied in a real rolling process, and it was found that the effect of edge thermal spraying on flatness defects at the edges of the work roll was significant.