Abstract: With optimized process measures such as decreasing mold cooling intensity, improving water distribution of mold board and narrow face, prolonging the length of secondary cooling zones, properly increasing casting specific water flow rate and adjusting of water flow proportion of each secondary cooling zone,the quality of 360 mmx450 mm casting bloom of high strength weathering steel YQ450NQR1 obviously improved,the ratio of surface depression defect decreased from 37. 13% to2.87%,the ratio of center porosity rating ≤1.0 increased from79.71% to90.70%,the ratio of center segregation rating ≤0.5 increased from 1.45% to 44. 19%,and the ratio of center crack free increased from 39. 13% to 62.79%.

摘要： 通过降低结晶器冷却强度、优化结晶器宽窄面水量分配,延长喷水冷却区长度、适当增大连铸比水量、调整二冷区各回路的水量分配比例等优化工艺措施,高强耐候钢YQ450NQR1 360 mm×450 mm连铸坯质量明显提高,表面凹坑缺陷率由37.13%降至2.87%,中心疏松评级≤1.0级的比例由79.71%增至90.70%,中心偏析≤0.5级的比例由1.45%增至44.19%,无中心裂纹的比例由39.13%增至62.79%。

关键词: 耐候钢, 大方坯连铸结晶器冷却, 二冷控制, 质量控制