Interaction behaviour between alumina particles and solidification front and particle behaviour in iron based alloys at deoxidation by Kirkendall effect

The present paper deals with interaction phenomena by particles in liquid metals. The interpretation is to make an initial analysis how the model by Kirkendall, for diffusion phenomena in solids, can be used for the analysis of particle behaviour in liquids. Whenever there is an unequal solutal field, insoluble particles may 'move' due to concentration gradients in the liquid and a difference of diffusion rates of the solute atoms. The analysis deals with the following melt/particles interactions: one is the interaction behaviour between the solidification front and the formed slag oxide particles of Al2O3 and the critical velocity for pushing/engulfment at the interface and the other is the movement and clustering of precipitated alumina inclusions around SiO2 or FeO inclusions formed in a steel melt before deoxidation. Despite the uncertainty of the used material constants and the assumed concentration profiles, the results of the present study are in accordance with some shown experimental particle movements.
5th Decennial International Conference on Solidification Processing Location: Univ Sheffield, Sheffield, England, Date: JUL 23-25, 2007