摘要
The carbon segregation that occurs in a round billet leads to instability in the anti-sulfur steel pipe.The maximum difference in the C content of these billets can reach 0.08%,and the equiaxed grain ratio is about 37.0%.In this paper,reasonable casting and mixing parameters were obtained by a study of the casting process,mold electromagnetic stirring,and the final electromagnetic stirring process.First,a mathematical model was established for the solidification and heat transfer of round-billet continuous casting using the characteristics of the continuous-casting process for sulfur-resistant steel pipes.The relationship between the casting speed,cooling-water ratio,and thickness of the shell at the final stirring position was analyzed.Then,the electromagnetic force and the liquid steel flow velocity were simulated and used to obtain reasonable parameters for the mold and final electromagnetic stirring.Through optimization of the casting and electromagnetic stirring technologies,the equiaxed grain ratio of the continuous-casting round billet increased to 53.4%and the maximum difference in the C content of the billet reduced to 0.031%.
