The Numerical Simulation Study Of Soft Reduction For Slab Continuous Casting

The centerline segregation and porosity have reduced greatly the internal quality of the continuous casting products. The soft reduction technique is one of the effective methods by forcing on the solidifying terminal at the solidifying terminal to improve the internal quality in the continuous casting of bloom. Studying and establishing craft parameters of soft reduction reasonably is an important means to prevent the internal defect and improve the slab quality in slab continuous casting successfully.According to the actual situation of slab casting's product line in Shouqin Metal Material Limited Company, the finite element method model of solidification and heat transfer in slab continuous casting has been developed. Parameters of thermophysical properties, the basic mechanics parameters and boundary condition were ascertained. Account the temperature variation of slab in continuous casting. Solidification principle and liquid core shape of strand at the end of solidification was studied systemically. Regulate water flow density distribution of secondary cooling zone can achieve the shape of"一"at the end of solidification. It is more conducive to the soft reduction slab sustains force evenly, reduce the centerline cracks of solidification front greatly.The 3D finite element model of thermo-machanical coupling on soft reduction has been developed. The craft parameters, especially the region of soft reduction and soft reduced rate of slab continuous casting, affected stress and strain are researched. Based on the volume of liquid core slab, more reasonable amount of reduction allocation model are advanced. The research results demonstrated that the stress and strain of slab region under soft reduction is larger, when the central solid-phase ratio in the region of soft reduction and soft reduced rate is larger. When the central solid-phase ratio of reduction region is 0.7, stress of solidification front of slab corner reaches a maximum, internal crack is engendered easily. When the central solid-phase ratio of reduction region is larger than 0.8, slab surface cracks tend to increase greatly. It is harmful for the equipment of soft reduction. According to Stress-strain variation, choosing many segments and unlikeness soft reduced rate is more advantageous to prevent the form of internal defect in slab.