Review on interaction between slag, steel and inclusions in secondary steelmaking

The refining function of slags in ladle metallurgy comprises desulphurization and capture of inclusions, which are removed from the steel melt during the deoxidation procedure. This review explores the interactive dynamics between slag and steel, emphasizing the beneficial roles of slag in the metallurgy process, including its passive shrouding function to protect steel from atmospheric oxidation and heat losses. However, it also addresses the potential negative implications of slag, particularly as a source of reoxidation and harmful inclusions. Traditionally, inclusions in steel are seen as deoxidation products influenced by the steel composition, principally determined by deoxidizing agents like Al, Si, Mn, and Ca. Nonetheless, during extensive ladle treatment processes, the role of top slag evolves beyond passive inclusion capture to involve significant chemical interactions with the steel. This nuanced understanding of the slag-steel relationship is essential for improving the quality of steel produced, as it informs both operational practices and the design of metallurgical processes.