Research On Metallurgy Property And Application Of New Type Slag

Sulphur is disadvantageous to most steels. So desulphurization is a indispensable link to produce pure steels. In this paper the research includes two parts. Firstly, CaO-SiO₂-Al₂O₃-CaF₂ is chosen as the basic slag. Effects of adding additives to CaO-based slag on melting point, viscosity and desulphurization ability have been investigated. Secondly, aiming at the problem that refining slag adhering to the ladle immerged cover during LATS refining process in Baosteel Group Shanghai No.1 Iron & Steel Corp., effects of additives on ladle slag have been investigated. The results are illustrated as below.Adding BaO, Li₂O to CaO-based slag can effectively decrease the melting point and viscosity of slag. When ω(BaO, Li₂O) =15%, the melting point (1185℃, 1267℃ ) of slag are much lower than that (1326 ℃) of slag without additives, the viscosity (0.51Pa·s, 0.98 Pa·s) of slag at 1475℃ are much lower than that (1.79 Pa·s )of flux without additives.Adding BaO , Li₂O to CaO-based slag can improve the desulphurization rate. When ω(BaO)=15%-25% and ω(Li₂O)≥7.5%, the desulphurization rate is more than 90%. It is much higher than that(66.1%) without additive.