Influence of a transverse magnetic field on solidification structure during directional solidification

International audienceThree alloys were directionally solidified at low growth speeds under a transverse magnetic field. The results show that the application of the transverse magnetic field significantly modified the solidification structure. Indeed, we found that along with the refinement of cells/dendrites, the magnetic field caused the deformation of liquid-solid interfaces, extensive segregations (i.e., freckles and channels) in the mushy zone. Moreover, we observed that dendrite fragments and equiaxed grains were moved approximately along the direction perpendicular to the magnetic field. Modification of the solidification structure under a weak magnetic field is attributed to a TEMC-driven heat transfer and interdendritic solute transport and a TEMF-driven motion of dendrite fragments