Abstract: Through solidification simulation calculation and onsite test, the optimal soft reduction process parameters for continuous casting of non quenched and tempered steel were obtained. The No.1-5 reduction rollers perform a reduction of 3 mm-4 mm-5 mm-5 mm-3 mm, corresponding to continuous casting speed of 0.85 m/min,which improves the macro quality, while avoiding the emergence of pressing cracks. Based on the optimal process parameters of soft reduction and casting speed, the influence of electromagnetic stirring on segregation was studied. Combined with the actual equipment, the optimal electromagnetic stirring parameters were obtained through extreme value method experiments, the mould electromagnetic stirring current is 350 A, and the frequency is 2.0 Hz; the final electromagnetic stirring current is 200 A, and the frequency is 6 Hz. Finally, the carbon segregation index in the center of the billet can be controlled to be less than 1.10 by the multivariate coupling study of the process parameters of continuous casting.

Key words: simulation, soft reduction, electromagnetic stirring, carbon segregation