Phenomenological Comparative Research for the Effect of Fluid Flow on Characteristics of Solidification Structure of Continuous Casting Billet

In this study, the effect of liquid phase flow on the morphology of real solidification structure during the solidification process of the steel was studied by comparing the actual continuous casting billet with the thermal simulation sample structure of confocal laser scanning microscopy. The results show that the secondary dendrite arm spacing and fractal dimension of the solidification structure under continuous casting conditions are larger due to the existence of liquid phase flow. The positive changes of dendrite spacing and fractal dimension under liquid phase flow have an opposite effect on permeability, but in general, the permeability of the solidification structure obtained by the continuous casting process is larger. The influence of liquid phase flow can be reduced by reducing the dendrite arm spacing and increasing the fractal dimension. Moreover, increasing the cooling rate within a certain range can simultaneously reduce the dendrite arm spacing and increase the fractal dimension.