Abstract: The production flowsheet for MA ultra-low carbon steel (/% : ≤0.005C, 0.007-0.012Si, 0.07-0.15Mn, ≤0.025P, ≤0.025S, ≤0.035Als, ≤0.0020N) is KB-150 t BOF (end [C] ≤0.020%)-RH-200 mm slab CC flowsheet. The effect of mold flux, tundish shielding agent and ladle refractory materials on incremental carbon content in liquid has been tested and analyzed. Results show that the incremental carbon content in liquid in mold ( AC 0.0003%-0.0008% ) is obviously higher that in tundish (AC 0.0001%-0.0005% ) , through using the measures including defining metallurgy operation, controlling initial carbon content in mold flux 1% -2% and adding 3.5%-4.0% MnO₂ in flux, controlling the amount of tundish shielding agent, it is available to decrease the incremental carbon content in liquid.

Key words: MA Ultra-Low Carbon Steel, KB-150 t BOF-RH-CC Flowsheet, Mold Flux, Tundish Shielding Agent, Incremental Carbon Content in Liquid

摘要： MA超低碳钢（/%:≤0.005C,0.007~0.012Si,0.07~0.15Mn,≤0.025P,≤0.025S,≤0.035Als,≤0.0020N）的生产流程为KB-150 t BOF（终点[C]≤0.020%）-RH-200 mm板CC工艺。试验分析了结晶器保护渣,中间包覆盖剂,钢包耐火材料对钢液增碳量影响。结果表明,结晶器增碳量（△C 0.0003%~0.0008%）明显高于中间包增碳量（△C 0.0001%~0.0005%）,通过稳定冶金操作,控制保护渣原始碳量为1%~2%,向保护渣中添加MnO₂（3.5%~4.0%）,控制覆盖剂量等工艺措施,可有效地减少钢液增碳。

关键词: MA超低碳钢, KB-150 t BOF-RH-CC流程, 结晶器保护渣, 中间包覆盖剂, 钢水增碳