小方坯末端电磁搅拌位置的确定  

Position determination of the final-electromagnetic stirring of continuous billets

作　　者：宋方圆[1] 孙彦辉[1] 赵勇[1] 沈宏俊 段大波[1] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083

出　　处：《炼钢》2016年第3期29-34,共6页Steelmaking

基　　金：国家高技术研究发展计划(863计划)资助项目(2015AA03A502)

摘　　要：为提高某钢厂72A钢小方坯质量,减轻中心偏析,建立了小方坯凝固传热数学模型,基于现场射钉试验和铸坯表面温度测量结果对模型进行了修正,并利用修正的模型对小方坯连铸过程凝固传热行为进行了数值模拟,确定了最合理的末端电磁搅拌安装位置。模拟结果表明：当拉速由1.60m/min增加到1.90m/min时,电磁搅拌安装位置由7.26~7.64m后移到8.95~9.41m;当浇铸温度由1 485℃升高到1 498℃时,电磁搅拌安装位置由7.95~8.35m后移到8.17~8.61m。考虑到浇铸温度波动对电磁搅拌安装位置的影响,确立1.75m/min拉速下最佳的安装位置为距弯月面8.17~8.35m处。工业试验表明,当拉速为1.75m/min,末端电搅中心位置在8.25m处时,中心缩孔和疏松均由1.0级下降到0.5级以下,中心碳偏析指数由1.15下降到1.05以下,铸坯质量得到了明显改善。To improve the quality of continuous billets and reduce the central segregation of 72 Atire cord steel,mathematical model of solidification and heat transfer was developed,then the model was revised based on the results of pin shooting tests and temperature measurements.By using the above revised model and numerical simulating,the appropriate position of final-electromagnetic stirring（F-EMS）was determined.The results showed that,the appropriate position of finalelectromagnetic stirring（F-EMS）moved from 7.26-7.64 m back to 8.95-9.41 m when the casting speed increased from 1.60m/min to 1.90m/min,it also moved from 7.95-8.35 mback to8.17-8.61 m when the casting temperature increased from 1 485 ℃to 1 498 ℃.Considering the influence of the temperature fluctuations,the optimal position of F-EMS was at distance from liquid meniscus 8.17-8.35 mwhen the casting speed was 1.75m/min.The industrial tests showed that,when the casting speed was 1.75m/min,the center of F-EMS was at distance from liquid meniscus8.25 m,the center porosity grade and pipe grade both declined from 1.0to less than 0.5,the center carbon segregation index also decreased from 1.15 to less than 1.05,the quality of continuous billets had improved.

关 键 词：小方坯 数值模拟 中心固相率 末端电磁搅拌 

分 类 号：TF777.2[冶金工程—钢铁冶金]