开浇前中间包充氩对中碳铝镇静钢钢水洁净度的影响研究

STUDY ON THE EFFECT OF TUNDISH ARGON FILLING ON THE CLEANNESS OF MEDIUM CARBON Al-KILLED MOLTEN STEEL BEFORE CASTING

为探讨开浇前中间包充氩置换工艺对中碳铝镇静钢钢水洁净度的影响,设计了3种中间包充氩工艺方案,并定量分析了3种方案下钢中T.O质量分数和夹杂物变化。其中,方案1充氩时间较长,方案2充氩时间较短,方案3无充氩。结果表明,RH出站至CCM阶段,方案1~方案3钢中T.O质量分数的增幅分别为15.6%、18.5%和74.1%,钢中夹杂物数量密度的增幅分别为12.1%、40.2%和166.8%,Al_(2)O_(3)质量分数在10%以上的钙铝酸盐夹杂物数量密度的增幅分别为25.4%、62.0%和321.8%。开浇前采用中间包充氩工艺有利于减少开浇阶段钢水的二次氧化,且充氩时间越长,钢水受二次氧化的影响越小。

In order to explore the effect of tundish argon filling replacement process on the cleanliness of medium carbon Al-killed molten steel before casting,three types of tundish argon filling process experiments are designed,and the changes of T.O mass fraction and inclusions in molten steel are quantitatively analyzed.Among them,scheme 1 has a longer argon filling time,scheme 2 has a shorter argon filling time,and scheme 3 has no argon filling.The result show that from the end of RH refining to the CCM stage,the increase in T.O mass fraction in steels of schemes 1 to 3 is 15.6%,18.5%,and 74.1%,the increase in the quantity per unit of inclusions in steel is 12.1%,40.2%and 166.8%,the increase in the quantity per unit of calcium aluminate inclusions with an Al_(2)O_(3)mass fraction above 10%is 25.4%,62.0%,and 321.8%,respectively.The use of tundish argon filling process before casting is beneficial to reduce the secondary oxidation of molten steel in the casting stage,and the longer the argon filling time,the less the molten steel is affected by secondary oxidation.