Longitudinal cracks in continuously cast round billets occur when the thermal stress and phase transformation stress generated during the so
Longitudinal cracks in continuously cast round billets occur when the thermal stress and phase transformation stress generated during the solidification process of molten steel exceed the load-bearing limit of the billet shell. Furthermore, the billet’s own crystal structure and composition weaken its crack resistance, ultimately leading to the formation and propagation of longitudinal cracks in the weak areas. The main causes are related to the non-uniformity of the molten steel solidification process, the characteristics of the steel grade, and the poor plasticity in the high-temperature brittle range.