ABSTRACT

The influence of mould level instability during continuous casting on the unevenness of the initial solidified shell in hypo-peritectic steels has been investigated. Water model experiments and in-plant casting experiments revealed that mould level instability, which increases with increasing casting speed, is related to longitudinal cracking resulting from the unevenness of the solidification shell. A numerical model which considers the effect of mould level instability was developed and used to simulate the formation of the unevenness of the solidification shell and solidified shell deflections. The calculation results show that an increase in the non-uniform infiltration of mould flux increases the unevenness of the solidified shell. On the other hand, the unevenness of the solidified shell decreases due to mild cooling. Overall, the results of the plant tests and calculations show that non-uniform infiltration of mould flux dramatically affects air gap formation and the unevenness of the solidified shell.

摘要

研究了连铸过程中结晶器液位不稳定对亚包晶钢初始凝固壳不均匀性的影响。水模型实验和厂内铸造实验表明，结晶器液面不稳定性随着铸造速度的增加而增加，这与凝固壳不均匀引起的纵向裂纹有关。建立了考虑结晶器液面不稳定性影响的数值模型，并用于模拟凝固壳不均匀性和凝固壳挠度的形成。计算结果表明，保护渣不均匀渗透的增加会增加凝固壳的不均匀性。另一方面，由于温和的冷却，凝固壳的不均匀性降低。全面的，