RESEARCH OF THE PROCESS OF THE FORMATION OF SLAG INCLUDED IN BILLETS DURING THE CASTING OF A CONTINUOUS STEEL CASTING MACHINE

Abstract

For a long time, blanks with a defect, previously classified as slag entrapment, have been manufactured at the enterprise for grade MBLZ from different grades of steel. As a result, research was conducted to determine the root cause. Metallographic studies of workpiece defects are presented, showing that the cause of the defect is not only slag entrapment, but also cold drops and porosity. Different degrees of etching were used to conduct metallographic studies, and scanning electron microscope analysis was also performed. Based on the information available in the literature and on the basis of the thermodynamic model of the Fe-Si-Mn-O system, the mechanism and scheme of foaming and capture of slag inclusions in the crystallizer was carried out. Based on the results of the metallographic study, a mechanism for the formation and capture of cold drops and recommendations for reducing slag inclusions in the workpieces are proposed.