拉速对小薄板坯连铸结晶器内温度、溶质及夹杂物分布的影响

Effects of drawing Speed on Temperature, Solute and Inclusion Distribution in the Continuous Casting Mold of Thin Slab

采用数值模拟的方法,建立了140 mm×35 mm小薄板坯连铸过程的流场-温度场-溶质场-夹杂物的耦合数学模型,分析了拉速对结晶器内温度、溶质以及夹杂物分布的影响规律。结果表明,结晶器内溶质富集在固液两相区,在液相中逐渐降低,随着拉速增大,偏析最严重的区域向结晶器窄面靠近;夹杂物的体积分数、数量密度分布与结晶器内钢液的速度分布基本一致,在钢液流动方向上较高,在液相中不断降低。随着拉速增大,出口处夹杂物体积分数与数量密度变大,距离中心对称面越近,夹杂物体积分数与数量密度变化越显著。

The coupling mathematical model of flow field, temperature field, solute field and inclusion in the continuous casting process of 140 mm×35 mm thin slab was established by means of numerical simulation. The results show that the solute concentration in the crystallizer is in the solid-liquid two-phase region, and it decreases gradually in the liquid phase.With the increase of the drawing speed, the most severe segregation area is close to the narrow surface of the crystallizer.The distribution of volume fraction and quantity density of inclusions is basically consistent with the velocity distribution of molten steel in the crystallizer. With the increase of the drawing speed, the integral number and quantity density of the inclusion at the exit become larger, and the closer to the central symmetry plane, the change of the integral number and quantity density of the inclusion becomes more significant.