Effect of slag basicity adjusting on inclusions in tire cord steels during ladle furnace refining process

Abstract

Three heats of industrial trials and thermodynamic calculations were performed to investigate the effect of slag basicity adjusting on inclusions in tire cord steels. It was found that the application of low basicity slag can effectively avoid the formation of Al2O3-rich inclusions, while a high basicity slag was beneficial to improve the cleanliness of tire cord steels. It should be noted that adjusting slag basicity from 1.5–2.0 to 0.8–1.0 during the LF refining process can hardly lower the Al2O3 in inclusions. Thus, it was suggested to use the low slag basicity during the whole LF refining process to avoid the formation of Al2O3-rich inclusions. Moreover, thermodynamic calculation of slag-steel-inclusion reactions of tire cord steels was performed to better understand the observed experimental results.