9th ECCC European Continuous Casting Conference – ECCC 2017

The mold flux is the most important thing for the lubrication between the mold and initial solidification shell in continuous casting process. However, in the process, the mold slag generated by the mold flux is entrained into molten steel and brings about the surface defects of IF steel. Generally, in order to reduce the entrainment of the mold slag, continuous casting plants have tried to change the characteristics of the mold by reducing casting speed, optimizing molten steel flow control. In the present study, the defect mechanism in the mold is reviewed and the defect reduction technologies in the solidification process are discussed. In reducing the mold flux defect, interfacial tension between the slag and molten steel is important. As a result of laboratory experiments, the interfacial tension of the mold slag has changed according to the composition of the mold flux. Alkali-oxide has played a key role in increasing the interfacial tension of the mold slag. The result has been applied to a continuous casting plant and the number of the slag defects has reduced sharply.