Abstract: Production flow sheet for 1 550 mm x230 mm slab of steel A36 bearing B (/% : 0. 16 ~0. 20C, 0. 10 ~
0.25Si, 0. 20 〜0.40Mn, ≤0.030P, ≤0. 015S, 0. 010 〜0. 030Al, 0. 015 ~0. 025Ti, 0.001 0 ~0.001 8B) is hot metal pretreatment-210 t BOF-ladle argon blowing-LF-CC process. With the process measures including controlling [C] ≥ 0. 16% , increasing basicity of mold powder from 1. 23 to 1. 27 and decreasing its viscosity from 0. 165 pa • s to 0. 123 pa • s, decreasing negative shrip time from 0. 22 s to 0. 15 s as casting speed 1. 0 m/min, decreasing mold and cooling water rate of slab edge at straightening zone, improving accuracy of caster arc and roller gap, the comer transverse cracks are effectively reduced and the grinding rate decreases from original 0. 18% to 0. 03%.

Key words: Steel A36 Bearing B, 230 mm Cast Slab, Comer Transverse Crack, Mold Powder, Mold Oscillation, Cooling Scheme

摘要： A36含硼钢(/%:0.16～0.20C、0.10～0.25Si、0.20～0.40Mn、≤0.030P、≤0.015S、0.010～0.030Al、0.015～0.025Ti、0.001 0～0.001 8B)1 550 mm×230 mm板坯的生产流程为铁水预处理-210 t BOF-钢包吹氩-LF-连铸工艺。通过控制[C]≥0.16%,结晶器保护渣碱度由1.23提高到1.27,粘度由0.165 Pa·s降至0.123 Pa·s,在拉速1.0 m/min时负滑动时间由0.22 s降至0.15 s,降低结晶器和矫直段铸坯边部的冷却水量,控制铸机对弧精度和辊缝精度,铸坯表面未发现明显的横裂纹,铸坯的修磨量由0.18%降至0.03%。

关键词: A36含硼钢, 230 mm板坯, 角部横裂纹, 保护渣, 结晶器振动, 冷却制度