【摘要】 通过在160 mm×200 mm连铸机上进行的试验,研究了结晶器电磁搅拌对45钢方坯凝固结构的影响。研究表明,同一频率下,随搅拌电流强度的增加,铸坯的等轴晶率明显增加;电流强度不变时,随着频率的增加,等轴晶率基本保持不变;并讨论了衡量电磁搅拌效果的指标问题,通过分析磁感应强度、电磁扭矩与电磁搅拌参数的关系可以得出,铸坯等轴晶率变化趋势与电磁扭矩变化趋势有良好的一致性,电磁扭矩比磁感应强度更有效地反映电磁搅拌效果,前者更真实地衡量了电磁搅拌对钢液的搅拌强度,随着搅拌强度的提高,铸坯等轴晶率提高。通过研究,优化了结晶器电磁搅拌工艺,使铸坯等轴晶率达60%以上,改善了中心碳偏析,降低了疏松及缩孔程度。更多还原

【Abstract】 Effect of mould electromagnetic stirring(M-EMS) on solidification structure of 45 steel billet was studied by testing in 160 mm×200 mm continuous caster.The results showed that equiaxed crystal ratio increased obviously with increase of electromagnetic intensity of M-EMS,but the equiaxed crystal ratio did not changed with increase of frequency of M-EMS.The indexes for effecting electromagnetic stirring were also discussed by analyzing the relationship between magnetic flux density,electromagnetic torque and parameters of M-EMS.The change trend of equiaxed crystal ratio was accord well with the change trend of electromagnetic torque.That is to say,electromagnetic torque can reflect the effect of electromagnetic stirring in billet more effectively than magnetic flux density.Electromagnetic torque is the real index for measurement the stirring strength of steel by electromagnetic stirring technology,and equiaxed crystal ratio is increased with increase of the stirring strength of steel.The process of M-EMS was optimizing after this study,which make equiaxed crystal ratio of 45 steel billet increased to more than 60%,the carbon segregation improved,and the porosity and shrinkage cavity reduced.更多还原