Application of slag tracers to investigate source of non-metallic inclusions

摘要

In the present paper, different trials using BaO as a ladle slag tracer were performed to investigate the role of slags on the formation of non-metallic inclusions. Results of these trials showed that the ladle slag may actively contribute to the generation of inclusions. In those heats where the tracer was added it was found that about one-third of the large inclusions detected in the final product had BaO in their composition. These inclusions may be generated by emulsification of the ladle slag during the refining stage at the ladle furnace. Additionally, inclusions containing BaO were also obsefved in some of the heats processed with the same ladle that previously had been used with traced slags. This fact suggests that the slag layer that remains stuck to the ladle wall after finishing the heat may be a source of inclusions for the next heat.