Abstract:
The cracks appearance on slab edge is a significant quality problem faced in the rolling process. In this paper, an energy analytic model to evaluate the growth and closure of edge crack in vertical rolling process is established. According to the proposed
Γ-cubic function dog-bone model, the corresponding expressions of plastic flow velocity field, strain rate field, as well as total power functional with crack size parameters are obtained. The calculation of critical crack point is achieved after dog-bone deformation parameters and rolling force are solved numerically by using the principle of minimum energy. Then, the established calculation method is verified by specific examples. Furthermore, the effects of crack size on rolling parameters and mechanical properties are studied. The results show that the growth of crack is related to the deformation degree of the slab edge. For the premise of width reduction requirement, increasing the radius of vertical rollers is an advantage to control the edge crack and improve the crack closure rate. This paper provides an insight into ensuring product quality and the optimization of rolling process.