Abstract: The process of RH deoxidization of W470 non-oriented silicon steel was optimized in Shasteel. The results showed that the total oxygen content of liquid steel at RH end was reduced from (20－30)×10-6 to (15－20) ×10-6. Due to reducing the oxidation of silicon and manganese during the alloying process, the inclusions containing SiO2 and MnO reduced rapidly. The inclusion density of slab and the largest size of inclusion observed by SEM decreased by a large margin. As a result of the secondary oxidation of liquid steel caused by the ladle slag, there was still a large number of inclusions with small size. Besides, the yield of silicon and manganese increased evidently.

Key words: non-riented silicon steel, RH deoxidization process, high aluminum inclusion, secondary oxidation