非调质钢连铸关键技术的开发与应用

Development and application of key technology in continuous casting of non quenched and tempered steel

通过凝固仿真模拟计算结合现场试验得出了非调质钢最优的连铸轻压下工艺参数:1~5号拉矫辊执行3 mm-4 mm-5 mm-5 mm-3 mm的压下量,对应连铸拉速0.85 m/min,在提高铸坯低倍质量的同时,避免了压下裂纹的出现。在最优轻压下、拉速工艺参数的基础上研究了电磁搅拌对偏析等的影响,结合设备实际采用极值法试验得出了最佳的电磁搅拌参数:结晶器电磁搅拌电流350 A,频率2.0 Hz;末端电磁搅拌电流200 A,频率6 Hz。最终通过对连铸工艺参数的多元耦合研究,可以控制铸坯中心碳偏析指数不大于1.10。

Through solidification simulation calculation and onsite test,the optimal soft reduction process parameters for continuous casting of non quenched and tempered steel were obtained.The No.1-5 reduction rollers perform a reduction of 3 mm-4 mm-5 mm-5 mm-3 mm,corresponding to continuous casting speed of 0.85 m/min,which improves the macro quality,while avoiding the emergence of pressing cracks.Based on the optimal process parameters of soft reduction and casting speed,the influence of electromagnetic stirring on segregation was studied.Combined with the actual equipment,the optimal electromagnetic stirring parameters were obtained through extreme value method experiments,the mould electromagnetic stirring current is 350 A,and the frequency is 2.0 Hz;the final electromagnetic stirring current is 200 A,and the frequency is 6 Hz.Finally,the carbon segregation index in the center of the billet can be controlled to be less than 1.10 by the multivariate coupling study of the process parameters of continuous casting.