A review on prediction of casting defects in steel ingots: from macrosegregation to multi-defect model
Jun Li1,2, Xiao-wei Xu1, Neng Ren1, Ming-xu Xia1,2, Jian-guo Li1
1 School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; 2 Shanghai Key Laboratory of Advanced High-Temperature Materials and Precision Forming, Shanghai 200240, China
A review on prediction of casting defects in steel ingots: from macrosegregation to multi-defect model
Jun Li1,2, Xiao-wei Xu1, Neng Ren1, Ming-xu Xia1,2, Jian-guo Li1
1 School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; 2 Shanghai Key Laboratory of Advanced High-Temperature Materials and Precision Forming, Shanghai 200240, China
摘要 Due to the nature of the solute redistribution, the reduction in the solidification rate with time in a square root relationship, and the multiphase melt flow during the solidification, casting defects such as macrosegregation, shrinkage cavity, and porosity will inevitably occur in the steel ingot and intensify with the increase in ingot size. These defects directly affect the performance of the final product and severely restrict the choice of subsequent thermal processing methods and process windows. Therefore, the solidification defects including macrosegregation, shrinkage/porosity, and inclusions encountered in the preparation of large steel ingots and their formation mechanisms were reviewed. The development progress and the latest development of the macrosegregation model for steel ingots were introduced in detail, especially the latest progress in the coupling prediction of macrosegregation and shrinkage as well as macrosegregation and inclusions. Some methods to reduce macrosegregation of ingots were discussed as well. Finally, a new casting method called layered casting was introduced in detail. This method can effectively improve the uniformity of the macrostructure and reduce the macrosegregation of the large ingots and therefore is a promising method for preparing large ingots with high homogeneity.
Abstract：Due to the nature of the solute redistribution, the reduction in the solidification rate with time in a square root relationship, and the multiphase melt flow during the solidification, casting defects such as macrosegregation, shrinkage cavity, and porosity will inevitably occur in the steel ingot and intensify with the increase in ingot size. These defects directly affect the performance of the final product and severely restrict the choice of subsequent thermal processing methods and process windows. Therefore, the solidification defects including macrosegregation, shrinkage/porosity, and inclusions encountered in the preparation of large steel ingots and their formation mechanisms were reviewed. The development progress and the latest development of the macrosegregation model for steel ingots were introduced in detail, especially the latest progress in the coupling prediction of macrosegregation and shrinkage as well as macrosegregation and inclusions. Some methods to reduce macrosegregation of ingots were discussed as well. Finally, a new casting method called layered casting was introduced in detail. This method can effectively improve the uniformity of the macrostructure and reduce the macrosegregation of the large ingots and therefore is a promising method for preparing large ingots with high homogeneity.
Jun Li,Xiao-wei Xu,Neng Ren, et al. A review on prediction of casting defects in steel ingots: from macrosegregation to multi-defect model[J]. Journal of Iron and Steel Research International, 2022, 29(12): 1901-1914.
2022, Vol. 29 
