Motion Behavior of Nonmetal Inclusions at the Interface of Steel and Slag. Part II: Model Application and Discussion

Based on a mathematical model for the dynamics of inclusions at the steel-slag interface, this study discusses the influences of interfacial tension, inclusion diameter, and slag viscosity on the movement and removal of inclusions at the interface. The results show that (1) the greater the interfacial tension, the smaller the rate of displacement that inclusions move and the longer the separations time needed; when inclusions fully permeate the slag phase, residence and separation times at the interface will lengthen as inclusion diameter increases. For very high interfacial tension, inclusions cannot enter the slag layer; instead, they oscillate across the interface between molten steel and slag phases. The greater the inclusion size, the more pronounced are the oscillations. (2) The interfacial tension shows no effect on the rebounding of inclusions, but only impacts the separation and removal of inclusions. (3) With increasing slag viscosity, the velocity with which inclusions enter the slag layer slows; as a result, the displacement in the slag layer shortens, until inclusions are able to separate and enter the slag layer. Under this condition, slag viscosity has no effect on the maximum displacement of inclusions in the slag layer.