换包后中间包内夹杂物运动行为

采用数值模拟与工业试验相结合的研究方法,分析中间包在换包后包内夹杂物颗粒在非等温条件下的运动行为。研究结果表明,换包后,钢中不同尺寸的夹杂物有分离趋势,且小于50μm夹杂物的去除条件逐渐变差。在浇注中后期,小于50μm夹杂物倾向于跟随流体沿中间包底部流出中间包,夹杂物的去除效果进一步变差。工业试验结果表明,通过在中间包底部吹入氩气的方式,改善了换包后夹杂物去除的不利影响。中间包底吹氩气前,大于50μm夹杂物的数量密度为0.008 8个/mm~2;中间包底吹氩气后,铸坯中大于50μm夹杂物的数量密度为0.002 5个/mm~2。

Inclusions Movement Behavior in Tundish after Ladle Changing

With numerical simulation and industrial experiments,inclusions movement behavior in tundish under non-isothermal condition had been analyzed.Numerical simulation indicates that inclusions with different sizes tend to separate after ladle changing during continuous casting process,and inclusions with size lower than 50 μm are getting difficult to remove.During the middle and later period of casting process,inclusions with size lower than 50 tn tend to move along tundish bottom,and inclusions removing condition further worsens.Industrial experiments results show that by means of argon-blowing at tundish bottom,inclusions removing condition is improved.Average T.O] content in tundish is reduced by 3.5 ppm,and nitrogen content is reduced by 3ppm.Before argon-blowing,inclusions quantity density of slab is about 0.008 8/mm2,and reduced to 0.002 5/mm2.after argon-blowing.