Q345钢宽板坯连铸凝固末端位置的研究  

Study on final solidification point of continuous casting Q345 Steel wide slab

作　　者：成日金[1] 王志衡 倪红卫[1] 张华[1] 王洪富 夏金魁 曹龙琼 

机构地区：[1]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,湖北武汉430081 [2]武汉钢铁集团鄂城钢铁有限责任公司炼钢厂,湖北鄂州436002

出　　处：《炼钢》2013年第2期66-70,共5页Steelmaking

摘　　要：根据武汉钢铁集团鄂城钢铁有限责任公司Q345钢宽板坯实际生产条件,建立宽板坯凝固传热数学模型来确定其凝固末端位置,并采用射钉法验证及修正。结果表明:射钉试验测量结果与凝固传热数学模型结果误差在±1.3%以内,模型计算结果能真实反映此钢种宽板坯凝固末端位置。在典型拉速1.15 m/min下,200 mm厚宽板坯两相区位于距结晶器液面13.32～20.95 m处;在典型拉速0.95 m/min下,250 mm厚宽板坯两相区位于距结晶器液面16.16～23.45 m处;在典型拉速0.80 m/min下,300 mm厚宽板坯两相区位于距结晶器液面19.34～27.65 m处。不同拉速及铸坯厚度下,凝固末端位置差别较大。采用优化的轻压下技术后,Q345宽板坯中心偏析Ⅰ级内平均合格率由85.4%提高到99.5%。A solidification heat transfer mathematical model of wide slab is established based on practical production conditions of Q345 steel wide slab in Echeng Steelmaking plant to determine final solidification point. Besides, it is tested and modified by pin-shooting technique. The results show that the relative error between the results measured by pin-shooting technique and the results calculated by solidification heat transfer mathematical model is within 1.3 %, so the results calculated by solidification heat transfer mathematical model can reflect final solidification point of Q345 steel wide slab truthfully. In typical speed of 1.15 m/min, the mushy zone of 200 mm thickness wide slab is 13.32～20.95 m far from mold liquid level. In typical speed of 0.95 m/min, the mushy zone of 250 mm thickness wide slab is 16. 16～23.45 m far from mold liquid level. In typical speed of 0.80 m/min, the mushy zone of 300mm thickness wide slab is 19. 34～27. 65 m far from mold liquid level. The final solidification point is very different at different casting speed and slab thickness. After continuous casting process opti- mization the qualified percentage for central segregation in Q345 steel wide slab within rating I increases from 85.4% to 99. 5%.

关 键 词：宽板坯 凝固末端 数学模型 射钉法 

分 类 号：TF777[冶金工程—钢铁冶金]