Numerical Modeling of Grain Structure in Continuous Casting of Steel

Abstract

A numerical model is developed for thesimulationofsolidificationgrain structurefor- mation (equiaxed to columnar and columnar to equiaxed transitions) during the continuous cast- ing process of steel billets. The cellular au- tomata microstructure model is combined with the macroscopic heat transfer model. The cellular automata method is based on the Nastac's defini- tion of neighborhood, Gaussian nucleation rule, and KGT growth model. The heat transfer model is solved by themeshless techniqueby using local collocation with radial basis functions. The mi- croscopic model parameters have been adjusted with respect to the experimental data for steel 51CrMoV4. Simulations have been carried out for nominal casting conditions, reduced casting temperature, and reduced casting speed. Proper response of the multiscale model with respect to the observed grain structures has been proved. Keyword: continuous casting of steel, solidifi- cation, multiscale modeling, equiaxed to colum- nar transition, columnar to equiaxed transition, macroscopic model, microscopic model, heat transfer model, cellular automata model, mesh- less methods.