开浇前中包充氩对圆坯钢水洁净度的影响

The Effect of Tundish Argon Filling before Casting on the Steel Cleanliness of Round Billets

为研究开浇前中包充氩工艺对圆坯钢水洁净度的影响,设计了三种开浇前中包充氩工艺试验,量化分析了三种工艺条件下全氧及夹杂物的变化。结果表明,RH出站至CCM1期间,方案1~3钢中T.O分别增加16.3%、19.1%和77.6%,w(Al_2O_3)在10%以上的钙铝酸盐夹杂物数量密度分别增加26.8%、63.9%和345.1%,充氩炉次与不充氩炉次钢中夹杂物数量密度分别增加11.90%和211.78%,开浇前采用中包充氩有利于降低开浇阶段钢水的二次氧化,且充氩时间延长可进一步降低钢水的二次氧化,但考虑到中包充氩对中包温度的影响,建议开浇前中包充氩时间控制在3~5min。

In order to analyze the impact of tundish argon filling on billet steel cleanliness before casting, three ar-gon filling process tests before casting were designed and the changes of total oxygen and inclusions were quantitative-ly analyzed. The results showed that during the process from the end of RH refining to CCM1, the total oxygen in steel of program 1-3 increased by 16.3% , 19.1%, and 77.6%, respectively, and the number density of calcium aluminate inclusions containing more than 10% ofw（AI203） increased by 26.8%, 63.9% and 345.1%, respectively. The num-ber density of inclusions with and without argon filling increased by 11. 90% and 211. 78% , respectively. Adopting tundish argon filling before casting can reduce the secondary oxidation and longer time of filling can further reduce sec-ondary oxidation of steel, but considering the effect of argon filling on tundish temperature, the argon filling time should be controlled within 3-5min.