Numerical investigation of the influence of forced convection induced by a travelling magnetic field during solidification of metallic alloys

A. Noeppel¹ - O. Budenkova^1,2 - Y. Fautrelle¹

¹ SIMAP/EPM, Polytechnic Institute of Grenoble, France
² Ioffe Physico-Technical Institute, St.-Petersburg, Russia

Abstract
Two-dimensional axisymmetric numerical simulations of Bridgman solidification of a binary alloy Al-Ni~3.5 wt\% under forced convection induced by a travelling magnetic field (TMF) are performed. It is found that the TMF promotes segregation through the formation of a large channel, which can appear either at the center of an ingot or at its periphery. Position of the channel depends on the direction of applied magnetic force that corresponds to results of earlier experiments. A phenomenon of instability due to the competition between natural and forced convection in the mushy zone influencing the shape of the channels has been demostrated. Tables 2, Figs 3, Refs 16.