Finite element study of the effect of some local defects on the risk of transverse cracking in continuous casting of steel slabs

This paper introduces a numerical 2.5D model of continuous casting of steel slabs. This model is based on the finite element method and it has been applied to the study of some local defects in a continuous caster, such as partial blockage of nozzles (leading to a local reduction of secondary cooling rate), locking or misalignment of rolls. The purpose of the study was the evaluation of the effect of such defects on the risk of transverse cracking during bending and unbending operations. To do so, the simulation at macro-scale of the complete process has been first performed in standard conditions to get reference values and then each defect has been introduced. Defining two indexes (indicators) of the risk of transverse cracking, it has been possible to classify the defects in terms of risk increase, helping steel producers to focus on the most critical problems.