| Slab products are mainly used for industries like shipbuilding, household appliances and automobile. With the requirement of production properties and qualities from market gradually improved, which need to produce better slab products. In order to improve slab quality, nowadays it’s an important method to use electromagnetic stirring on secondary cooling zone of slab continuous casting. So nowadays it’s a research hotspot how to preferably improve slab quality through using slab electromagnetic stirring at home and abroad.This research used patented product which is about electromagnetic stirring in secondary cooling zone of slab continuous casting of one inland steel plant as research object, combined with problems of slab quality occurred in real plant, in order to research how it influence slab quality, methods including theory, simulation, experiment were adopted. The metallurgical principle of how electromagnetic stirring in secondary cooling zone of slab continuous casting influence slab quality was studied. In virtue of the software ANSYS, finite element mathematical models of electromagnetic stirring in secondary cooling zone of slab were established, the process was simulated. On this basis the best parameters were obtained to conduct experimental analysis, seeking the best process parameters of electromagnetic stirring, by contrastive analysis on the quality of slab products, then optimizing the stirring effect of electromagnetic stirring in secondary cooling zone of slab continuous casting. Main research results as follows: (1) The research on metallurgical principle of how electromagnetic stirring in secondary cooling zone of slab continuous casting influence slab quality shows that: Through mingling hot and cold molten steel, electromagnetic stirring in secondary cooling zone can accelerate the disappearance of superheat degree, it also rinse freezing interface and cut off dendritic endings to form isometric crystal core, and refine isometric crystal then enlarge the isometric crystal zone, the central pipe, center segregation and inner cracks produced by superheat degree were reduced. (2) When the slab fracture surface was 200mm×1520mm, the numerical analysis on roll-type electromagnetic stirring in secondary cooling zone of slab continuous casting shows that:When model stirring current intensity was 380A, by changing the stirring frequency respectively at 5Hz,6Hz,7Hz,8Hz,9Hz, electromagnetic field mainly kept at the same distribution, the electromagnetic force increased with the increase of frequency, but magnetic induction intensities decreased with the increase of frequency; When model stirring frequency was 8Hz, by changing the current intensity respectively at 350A,360A,370A,380A,390A, electromagnetic field mainly kept the same distribution, however, the magnetic induction intensities and electromagnetic force all increased with the increase of current intensity; This simulation indicate that the increase of current intensity and stirring frequency can enhance the electromagnetic force, in consideration of electromagnetic metallurgical effect, it’s better to choose 380A as and 8Hz as stirring frequency current intensity.(3) The experimental research on effect of the electromagnetic stirring to the quality of slab shows that:When the chosen current intensity was 380A, stirring frequencies chosen in this experiment respectively were 5Hz,6Hz,7Hz,8Hz,9Hz, other technological parameters were in the same conditions, when EMS frequency was 8Hz, the electromagnetic stirring has the best effect, the central equiaxed zone ratios reached the best value, the central porosity are entirely controlled level 0.5 and the central segregation are entirely controlled less than level C1.5, so the best frequency chosen was 8Hz. When the stirring frequency was 7Hz, the stirring electricity respectively were 350A,360A and 380A, the stirring effect of 380A was the best. However, it’s effect was worse compared with the stirring effect of which frequency was 7Hz and electricity was 380A. So the best choice of stirring electricity will be 380A. With the overall consideration of simulation and experiment results the best stirring electricity and stirring frequency are 380A and 8Hz.
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