Detection and Numerical Simulation of Non-Metallic Inclusions in Continuous Casting Slab

A high-efficiency fast-detection platform (FDP) is set up to detect the spacial distribution of non-metallic inclusions in slab. The spacial distribution of inclusion in the slab is asymmetrical and non-uniform. In the vertical part of the caster, more inclusions are found in the loose side; while in the bending part, more inclusions are found in the fixed side. Two main sources of inclusions are revealed through SEM + EDS method: slag entrapment and oxidation of molten steel. The reason for these large inclusions is because of the high super heat and excessive rate of water cooling, since the micro structure is proven to be Widmanstatten. Then, a large eddy simulation (LES) model coupled with solidification is developed to study the inclusion transport and entrapment in the mold. Results show that the velocity near the fixed side is larger than that in the loose side, leading to the fact that more inclusions are removed from the top surface at the fixed side. Smaller inclusions are easier taken deep into the bending part of the caster, and are dragged by the curvature of fixed side, leading to the fact that inclusions in the fixed side are more than that in the loose side.