顶底复吹转炉冶炼不锈钢还原期行为研究

BEHAVIORS OF STAINLESS STEEL IN REDUCTION PERIOD IN COMBINED BLOWN CONVERTER

本文分析20t-STB复吹转炉冶炼不锈钢的还原期行为,得到lg(Cr)_s=4.483-7487/T-0.358lg[％Cr]-0.142lg[％Si]-1.428lgV-0.038lgQ_(Ar)。控制还原期碱度大于1.65、t<1650℃、[Si]_终>0.4％,对铬氧化物的还原比较有利。还原期[O]与[Si]相平衡,t、[Si]、α_(SiO_2)与钢液氧化性的关系近似服从热力学平衡式。Walsh的SiO_2活度计算式适用于复吹转炉冶炼不锈钢还原期[Si]-[O]平衡计算。

In this paper, the behaviors of stainless steel in reduction period in 20 t STB combined blown converter is analysed. A formula is obtained: (%Cr)_s=4.483-7487/T-0.358lg[%Cr]-0.142 lg[%Si]-1.428lg V-0.038lg Q_(Ar). The results show that chromium oxide is reduced more effectively when basicity>1.65,t<1650℃ and [Si] end>0.4%. During the reduction period, [O] and [Si] are under equilibrium conditions, the relation among t, [Si], asio_2 and oxidizing character of hot metal approximately obeys thermodynamic equation and Walshs formula about the activity of silica is suitable for the [Si]-[O] equilibrium calculation.