过热度对高碳钢小方坯宏观偏析影响研究

摘要：基于国内某厂高碳钢小方坯连铸生产过程，首先利用ProCAST软件进行过热度对连铸坯宏观偏析影响的模拟研究，然后对过热度分别为44、39和28℃的连铸坯横断面和纵截面进行宏观偏析和疏松缩孔的研究。模拟结果表明:连铸坯横断面中心碳偏析随着过热度的增加不断增大，过热度超过25℃时，连铸坯横断面中心碳偏析度更加严重；试验结果表明，过热度分别为44、39和28℃ 的连铸坯横断面中心碳最大偏析度分别为1.39、1.32和1.06。结合模拟结果能够有效指导实际生产过程中连铸参数的调整，过热度越高，连铸坯中心碳偏析、条带状疏松缩孔越严重，为了降低连铸坯宏观偏析，建议将过热度控制在25~30℃。

Effect of superheat on macrosegregation in high carbon steel billet during continuous casting process

Based on the production process of continuous casting for the hard wire steel billet in a domestic factory, firstly, the ProCAST simulation software was used to study the effect of superheats on the macrosegregation of the continuous casting billet. The macrosegregation, porosity and shrinkage of the cross section and longitudinal section of the continuous casting billet with the superheat of 44, 39 and 28℃ were carried out, respectively. The simulation results show that the segregation of carbon in the center of the cross section of continuous casting billet continues to increase with the increase of superheat. When the superheat exceedes 25℃, the segregation of the center carbon in the cross section of continuous casting billet becomes more serious. The industrial test results show that the maximum segregation degree of carbon for the cross sectional center of the continuous casting billet with the superheat of 44, 39 and 28℃ was 1.39, 1.32, and 1.06, respectively. The simulation results can effectively guide the adjustment of the continuous casting parameters during the actual production process. Meanwhile, the higher of the superheat, the more serious of the segregation of carbon and the strip shaped porosity and shrinkage cavity in the center of the continuous casting billet. In order to reduce the macrosegregation of the continuous casting billet, it is recommended to control the superheat between 25℃ and 30℃.