大型钢锭充型和凝固过程的数值模拟

Numerical Simulation of Filling and Solidification Process of Large Steel Ingot

采用铸造CAE软件对25t钢锭的充型和凝固过程进行了数值模拟与分析,并用生产现场的实测数据对模拟结果进行比较,验证了模型的适用性。探讨了大型钢锭在凝固过程中温度场的变化规律,对钢锭中可能存在的缺陷及位置进行了预测。通过数值模拟发现,冒口容积偏大,冒口补缩效果较好,锭身没有宏观缩孔,但轴线缩松仍然存在。可适当降低冒口容积,并在后续生产中增加搅拌,以消除中心偏析,提高钢锭质量。根据模拟显示的钢锭完全凝固时间,可将脱模时间提前到钢锭浇注完成后的6.4h。

The filling and solidification processes of a 25t steel ingot from a special steel plant were simulated by CAE software,and the numerical simulation results were compared with measured data from the practical production,and the feasibility of the model was verified.Solidification process of large steel ingot and the distribution of temperature field were analyzed.And the potential defects locations were forecast in the ingot.The results reveal that the larger riser size is helpful for the feeding,and macroshrinkage cavity is absent,however,shrinkage porosities along the axial can be observed.Through decreasing riser size and using stirring process in the subsequent process,central segregation can be eliminated to improve the quality of steel ingot.Based on the solidification time from simulation,the molddrawing time can be set 6.4 hours in advance after pouring steel ingot.