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为了定量把握结晶器中的钢水流动、钢水过热度及结晶器传热阻力对初期凝固坯壳的凝固不均一的影响，利用水冷铜板的浸渍实验，测定了各种铸造条件下的凝固坯壳厚度、凝固不均一度及树枝晶偏角；利用水力模型实验，并对实机铸坯的凝固组织分析，ＥＰＭＡ对负偏析带的线分析，得出了在结晶器中凝固坯壳上负偏析带的产生原因。其主要结果是：①随着钢水流动速度及过热度的增加，凝固坯壳厚度减少，凝固坯壳不均一度增大；②缓冷结晶器可有效地改善低碳钢初期凝固坯壳的不均一性；③在连铸坯表层（６～１０ｍｍ）存在的负偏析带产生于距弯月面２５０～４５０ｍｍ处，其生成原因是由于浸渍水口的吐出流所致。
In order to quantitatively grasp the influence of the molten steel flow in the mold, the superheat degree of the molten steel and the heat transfer resistance of the mold on the solidification unevenness of the initially solidified shell, the thickness of the solidified shell under various casting conditions , Solidification heterogeneity and dendritic declination angle. Based on the hydraulic model experiment and the solidification microstructure analysis of EPR slab and the line analysis of negative segregation zone by EPMA, the negative segregation zone The reason for the The main results are as follows: (1) With the increase of molten steel flow velocity and superheat, the thickness of the solidification shell decreases and the heterogeneity of the solidified shell increases. (2) Slow cooling crystallizer can effectively improve the initial solidification of the low carbon steel shell Homogeneity; ③ Negative segregation zone existing in the surface of continuous casting slab (6 ~ 10mm) occurred at 250 ~ 450mm from the meniscus, which is caused by the discharge flow of the immersion nozzle.