1. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; 2. HBIS Handan Iron and Steel Group Co., Ltd., Hadan 056015, Hebei, China; 3. State Key Lab of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, Hebei, China
Abstract：In the current study,the composition of IF molten steel and the properties of inclusions at different time in tundish during the continuous casting process were systematically analyzed to reveal the effect of tundish reoxidation on cleanliness of IF steels. The evolution mechanism of inclusions during the reoxidation of IF steels was aslo predicted by thermodynamic calculation. It was found that the reoxidation during the casting process was mainly caused by the absorption of air,increasing the Al2O3 content in inclusions. One part of alumina inclusions are formed by homogeneous nucleation,which results in the formation of more small Al2O3 inclusions in steels. The other part is of alumina inclusions are formed by heterogeneous nucleation, which results in the formation of a pure Al2O3 layer on the surface of the original Al2O3 core,and increase the size of the inclusions.
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