INTERACTIONS OF NON-METALLIC INCLUSIONS WITH STEEL AND SLAG: THERMODYNAMIC MODELING, EXPERIMENTS AND METALLOGRAPHIC ANALYSES

One aspect of an efficient process and product optimization of the liquid steelmaking process is the understanding of reactions and interactions between the components steel, slag and non-metallic inclusions. The present paper focuses on a fundamental study of this topic by combining the powerful methods of thermodynamic modeling with systematic experiments on a laboratory scale and subsequent SEM/EDS analyses. The modeling aspect is addressed by the commercial software FactSage 6.1; laboratory experiments are performed for a low-alloyed, Ca-treated carbon steel combined with varying slag compositions. The consequent SEM/EDS analyses provide a detailed insight into the inclusion landscape which offers a strong tool for characterizing the modification of inclusions. In the present study the combination of these methods is mainly applied to oxides, due to their crucial influence on the final product quality, thus giving important indications for further optimizing the secondary metallurgy processes.