The influence of electromagnetically-driven convection on temperature field and solute distribution during directional solidification

Solidification experiments as well as numerical simulations were carried out considering the directional solidification of Pb Sn alloys from a water cooled copper chill. A rotating magnetic field (RMF) was applied for melt agitation. The comparison between numerical simulations and solidification experiments delivered a good agreement. Our results disclose that the forced convection causes distinct modifications of the temperature and concentration field. The electromagnetic stirring promotes the columnar-to-equiaxed transition and causes a considerable grain refinement. Indications for a flow-induced fragmentation have been found in the microstructure of the stirred samples.