An Experimental Benchmark of Non-metallic Inclusion Distribution Inside a Heavy Continuous-Casting Slab

摘要

Different mathematical models were suggested to calculate the transport phenomena of non-metallic inclusions during continuous casting of steel, but there are no experimental data at the process scale available to evaluate the models. This paper is to provide an experimental benchmark to evaluate those models. It includes the most necessary casting process parameters for a heavy continuous-casting (CC) slab and the final result on the spatial and size distribution of macroscopic non-metallic inclusions (MNMIs) in the as-cast slab. The MNMIs with diameter larger than 50m inside the CC slab were in situ detected through a fast-detection platform (FDP). The casting sample (half width of the slab 1150mmx300mm of entire slab thicknessx75mm in casting direction) were ground slice by slice with the maximum resolution of 1mm; the morphology of the MNMIs was metallographically analyzed and the number of the MNMIs of difference size classes was counted; finally, the (3D) spatial distribution of MNMIs of difference size classes in the casting sample was reconstructed. Further information about the distribution of MNMIs was reported as well: (1) typical morphologies of independent nearly spherical MNMIs, bubble + NMIs, irregular-shaped MNMIs, and cluster MNMIs; (2) the size distribution of MNMIs along the thickness direction in both vertical section and bending section; (3) a probability number density function of MNMI diameter.