Center Segregation Evolution in Slab Continuous Casting with Mechanical Reduction: A 3D Simulation

A 3D model is built to simulate the transport behavior in the slab continuous casting with mechanical reduction. More importantly, the reduction amounts and reduction positions on the center segregation evolution are investigated. The model is verified by the measured solute segregation and surface temperature. The results show that liquid steel from the submerged entry nozzle (SEN) impacts the slab narrow surface directly, which reduces the solidified shell thickness in the edge part. In later solidification, the bulging amount of the edge part is larger than that of the middle part, which promotes solute-enriched liquid to move from middle part to edge part and results in serious segregation. When the reduction zone is set at 13-17 m from the meniscus, the center segregation of the middle part is reduced, but that of the edge part becomes more serious, due to the enriched liquid compressed to the edge part. The slab solidification end should be within the reduction zone, both for the middle part and for the edge part. The optimum reduction zone is from 15.0-17.0 m to 16.0-18.0 m, where center segregation in the edge part begins to decrease and that in the middle part remains at a lower level.