Evolution of inclusion nature during the EAF-LF-CC process

With the objective to improvement of the quality of steel, the evolution of the chemical composition and the population of inclusions were studied in an Electric Are Furnace-Ladle Furnace-Continuos Casting (EAF-LF-CC) route p rocess. In order to obtain reliable and consistent experimental information , a selected secondary treatment was compared with a new secondary treatmen t, which differed from the former by adding a synthetic slag during the EAF tapping stage. Samples from various steps of the process were analyzed to characterize the inclusions in terms of the chemical composition, size and volume fraction. The results observed for both practices were found to be v ery similar: both showed a great effect of the EAF tapping operation, after which a wide chemical composition variation of the inclusions was observed among the individual particles. The composition of the inclusions was obse rved to be less heterogeneous in subsequent stages. Additionally, the inclu sion population decreased throughout the subsequent process stages. The ana lysis of the inclusion population before and after their passage through th e tundish suggested an efficient hydrodynamic behavior of the liquid metal regarding the elimination of inclusions.