title: Positive segregation as a function of buoyancy force during steel ingot solidification.
abstract: We analyze theoretically and experimentally solute redistribution in the dendritic solidification process and positive segregation during solidification of steel ingots. Positive segregation is mainly caused by liquid flow in the mushy zone. Changes in the liquid steel velocity are caused by the temperature gradient and by the increase in the solid fraction during solidification. The effects of buoyancy and of the change in the solid fraction on segregation intensity are analyzed. The relationships between the density change, liquid fraction and the steel composition are considered. Such elements as W, Ni, Mo and Cr decrease the effect of the density variations, i.e. they show smaller tendency to segregate. Based on the modeling and experimental results, coefficients are provided controlling the effects of chemical composition, secondary dendrite arm spacing and the solid fraction.
authors.affiliation: Faculty of Metallurgy and Technology, University of Montenegro, Podgorica, Montenegro.
authors.forename: Zarko
authors.initials: Z
authors.lastname: Radovic
authors.affiliation: Faculty of Metallurgy and Technology, University of Montenegro, Podgorica, Montenegro.
authors.forename: Nada
authors.initials: N
authors.lastname: Jaukovic
authors.affiliation: Faculty of Metallurgy and Technology, University of Montenegro, Podgorica, Montenegro.
authors.forename: Milisav
authors.initials: M
authors.lastname: Lalovic
authors.affiliation: Faculty of Metallurgy and Technology, University of Montenegro, Podgorica, Montenegro.
authors.forename: Nebojsa
authors.initials: N
authors.lastname: Tadic
keywords: buoyancy effect; segregation; solidification; steel ingot