Regular Article

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

¹ Beijing Key Laboratory of Green Recycling and Extraction of Metals (GREM) and the School of Metallurgical and Ecological Engineering of University of Science and Technology Beijing (USTB), Beijing 100083, PR China
² Qingdao Iron and Steel Group Co. Ltd., Qingdao 266000, PR China

^* Email: zhanglifeng@ustb.edu.cn

Received: 16 June 2017
Received in final form: 6 July 2017
Accepted: 11 August 2017

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.