Al2O3夹杂物在钢-渣界面处的运动特性及去除率

通过理论计算和分析,研究了夹杂物颗粒在钢-渣界面处夹杂物去除层内的运动特性及去除率。结果表明:在夹杂物去除层内,Al2O3夹杂物颗粒的布朗扩散上浮临界尺寸为1.33μm,直径小于临界尺寸的夹杂物颗粒很难上浮去除;布朗碰撞的优势区域主要是直径为2.5μm以下的夹杂物颗粒之间以及直径为2.5～5μm夹杂物颗粒与0.5μm以下的微小颗粒之间的碰撞;直径为20～150μm的夹杂物颗粒在钢-渣界面去除层中9min内很容易完全上浮去除,而直径小于10μm的夹杂物颗粒去除率很低且升高缓慢,是提高钢液洁净度的主要控制对象。

Floating Critical Diameter and Removal Ratio of Al_2O_3 Particles in Interface Between Steel and Slag

The kinetic characteristics and removal rate of Al2O3 particles in the inclusion removing layer,which was close to the interface between steel and slag,were investigated by theoretical calculation and analysis.The results show that: the Brownian diffusion floating critical diameter(BDFCD) of Al2O3 inclusion particle is 1.33 μm,and the inclusion particle whose diameter is less than BDFCD is very difficult to be removed by floating;the Brownian collision dominant region is the area in which inclusion particles with diameter less than 2.5μm collide with each other and the inclusion particles with diameter of 2.5-5 μm collide with small ones with diameter less than 0.5 μm;the inclusion particles with diameter of 20-150 μm can easily be completely removed by floating in the inclusion removal layer,but the removal rate of inclusion particles with diameter less than 10 μm is very small and rise slowly,so these small inclusion particles are the main control objects to improve steel cleanliness.