摘要
结合连铸坯凝固规律及轻压下技术改善铸坯中心偏析的冶金原理,建立宽板坯轻压下率理论模型。根据某厂连铸宽板坯实际生产条件,以传热模型计算的铸坯凝固温度数据作为轻压下率模型计算条件,分析拉速、浇注温度、坯壳凝固收缩特性对铸坯轻压下率的影响规律。结果表明,在相同的拉速和浇注温度条件下,铸坯轻压下率沿拉坯方向的分布总体呈减小趋势;拉速较高时的起始轻压下率小于拉速较低时对应的起始轻压下率;拉速与平均轻压下率呈线性递减关系:拉速每升高0.1m/min,平均轻压下率减小0.015mm/m;浇注温度越低,轻压下区起始轻压下率的值越高;浇注温度对平均轻压下率的影响较小,浇注温度每升高10℃,平均轻压下率仅减小0.002 5mm/m;铸坯外部凝固坯壳的收缩对整个轻压下区平均轻压下率的贡献量为20.4%～22.3%。
This paper has derived soft reduction gradient model by using the solidification law of continuous casting strand and the metallurgical principle of soft reduction technology to improve centerline segregation.According to the production conditions of the wide slab in a certain plant,it analyzes the influence of casting speed,casting temperature,and solidification characteristics on the soft reduction gradient subjected to the strand temperature distribution and thickness of solidification shell which are calculated by heat transfer model.The main conclusions are as follows： the soft reduction gradient shows a decreasing trend along the casting direction when casting speed and casting temperature are the same;higher casting speed leads to lower initial soft reduction gradient,and casting speed has a linear decrease with the average reduction gradient;the average reduction gradient will decrease by0.015 mm/m when casting speed increases by 0.1 m/min;lower casting temperature corresponds to higher initial soft reduction gradient,and casting temperature has little influence on the average reduction gradient;the average reduction gradient will decrease by 0.002 5 mm/m when casting temperature increases by 10 ℃;the contribution of solidification shell to the total average reduction gradient is about 20.4%~22.3%.
出处
《武汉科技大学学报》
CAS
2011年第2期81-85,共5页
Journal of Wuhan University of Science and Technology
基金
湖北省自然科学基金资助项目(2009CDB358)
关键词
连铸
宽板坯
轻压下率
凝固前沿
continuous casting
wide slab
soft reduction gradient
solidification front
