Macro-micro modeling of the dendritic microstructure of steel billets processed by continuous casting

Operating data of a steel billet caster such as casting speed steel temperature and cooling conditions in the water spray zone are employed to predict dendritic microstructures of solidified steel. For that semi-empirical equations to calculate primary and secondary arm spacing were derived from uni-directional solidification experiments of steel samples with various compositions. When these equations are combined with a heat transfer model, which involves operating parameters of a caster, it is possible to predict dendritic microstructures, making possible micro-modeling from macro-processing data. Experimental measurements of primary and secondary arm spacing in four commercial steels agreed acceptably well by the predictions performed using this approach. The knowledge of microstructure will allow to pursue predictions of microsegregation phenomena.