研究了超低碳保护渣和液面波动等对钢水增碳的影响，通过数据对比分析两种保护渣的差异，发现保护渣是影响钢水增碳的主要因素，液面波动增大也加剧了钢水增碳程度。相应地采取控制钢水增碳的措施：减少保护渣中的自由碳质量分数，增加保护渣黏度，使熔渣层厚度由10～15 mm增加至15～20 mm；推进提高钢水纯净度，推进恒拉速浇注，减少了液面波动。通过以上措施的改进，保护渣A钢水增碳由4.0×10－6降低至0.8×10－6，保护渣B钢水增碳由2.4×10－6降至1.1×10－6，提高了生产控制水平，满足用户使用要求，同时降低了材料改判率。

The ultra-low-carbon steel may cause recarburization during continues casting process， because of the reaction between liquid steel and mold slag. The paper describes the effect of the mold slag and level fluctuation on the recarburization. As a result， the mold slag is the key factor in the steel recarburization， especially when the mold level fluctuates greatly. Therefore， some measures were taken to decrease the recarburization degree as follows. The molten slag layer was thicken by an increase in viscosity of the mold slag and a decrease in carbon content. The mold level fluctuates extent was tinier by keeping the casting speed steadier and liquid steel cleaner. As a result， the liquid steel recarburization of mold slag A was decreased from 4.0 ×10－6 to 0.8 ×10－6， and the liquid steel recarburization of mold slag B was decreased from 2.4 ×10－6 to 1.1×10－6， which improved the finished product rate and also met the customer’s demands better.