from the conferences organized by TANGER Ltd.
The performed tests were focused on the mechanism of reaction of Y2O3 and Al2O3 particles with the solidification front while casting steel. The presence of oxide inclusions in steel is a consequence of precipitation and segregation processes in the CCS CCM crystallizer. The oxide precipitations in the liquid metal are a result of deoxidization and are generally unfavorable for the future properties of steel; on the other hand, their fine dispersive phase may play the role of nucleation centers of other phases, which in this case is advantageous. Yttrium oxide precipitations are formed when yttrium is used as a modifier and micro additive to steel of definite properties. Unlike Al2O3, the resulting Y2O3 phase may be advantageous because it strengthens steel. Considerable differences between the density of aluminum oxide and yttrium oxide affect their interaction with the crystallization front. This will decide about the final distribution of inclusions in the cast ingot. Authors suggested a numerical solution with the use of own computer program. During computations a system of forces that acts on particle as well as physicochemical parameters of steel were taken into account. The calculations were performed in micro scale in reference only to one particle of a given radius, occupying different position with respect to the solidification front. The results of calculation were presented in the form of plots illustrating the change of position of the particle of a given radius with respect to its initial position.
Keywords: solidification front, Y2O3, Al2O3, numerical modelling, precipitation movement© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.