脉冲磁场去除钢中Al_(2)O_(3)夹杂物的研究

Study on removing Al_(2)O_(3) inclusions in steelby pulsed magnetic fields

为了探究脉冲磁场对钢中Al_(2)O_(3)夹杂物的去除效果,使用中频感应炉进行了熔炼实验。利用COMSOL多物理场软件对脉冲磁场作用下钢液流场和不同尺寸夹杂物的去除行为进行了数值模拟,将数值模拟与实验结果相结合,探讨了脉冲磁场作用对钢中Al_(2)O_(3)夹杂物的去除机制。实验发现,施加脉冲磁场处理后,钢中Al_(2)O_(3)夹杂物整体含量减少,小尺寸的Al_(2)O_(3)夹杂物数量百分比降低,大尺寸的Al_(2)O_(3)夹杂物数量百分比有所增加,表明施加脉冲磁场促进了Al_(2)O_(3)夹杂物的去除和碰撞长大。数值模拟结果表明,施加脉冲磁场处理时,钢液中形成上下双环流,促进了夹杂物的去除,且夹杂物尺寸越大,去除效率越高;同时,夹杂物大部分被分离至壁面,与实验观察结果一致。

In order to explore the effect of a pulsed magnetic field on the removal of Al_(2)O_(3)inclusions in steel,this paper carries out smelting experiments by using an intermediate frequency induction furnace.Then,numerical simulation of the flow field of molten steel and the removal of inclusions of different sizes under the action of the pulsed magnetic field is carried out through the software COMSOL multi-physics field.Combining the numerical simulation results with the experimental results,the removal mechanism of Al_(2)O_(3) inclusions in steel under the pulsed magnetic field is discussed.The experimental results show that,after the pulsed magnetic field treatment,the total content of Al_(2)O_(3) inclusions in steel decreases,the percentage of small-sized Al_(2)O_(3) inclusions decreases,and the percentage of larger-sized Al_(2)O_(3) inclusions increases,which indicates that the pulsed magnetic field promotes the removal and the collision growth of Al_(2)O_(3) inclusions.The numerical simulation results show that,when the pulsed magnetic field is applied,upper and lower double circulations form in the molten steel,which promotes the removal of inclusions.The larger the size of inclusions is,the higher the removal efficiency will be.Meanwhile,most of the inclusions are separated to the wall surface,which is consistent with the experimental results.