Meso-Segregations during Solidification in a Binary Alloy under the Influence of Convection

We present a numerical model aimed at simulating the segregations during the columnar solidification of a binary alloy. A validation experiment has carried out with a Sn-Bi10wt % in order to test the numerical model. The slow-cooling conditions have been used in order to promote the formation of segregation. Our objective is to study how the segregation characteristics in the mushy zone are influenced by laminar flows driven both by buoyancy and by AC fields of moderate intensity. It is shown that the electromagnetic forces create a flow field both in the liquid zone and in the mushy zone. In the laminar regime, the electromagnetically-driven flow doesn’t suppress the composition inhomogeneities, but may modify the segregation pattern, especially the freckle distribution