Effect of slowly rotating transverse magnetic field on a directionally solidified binary metallic alloy

The influence of a slowly rotating transverse magnetic field on the structure of directionally solidified binary metallic alloys was investigated. Thermoelectromagnetic convection (TEMC) exists near the solidification interface due to a temperature gradient and an applied magnetic field. The melt flow driven by superimposed electromagnetic stirring and thermoelectromagnetic convection and its effects on the structure of the directionally solidified alloy are studied. The magnetic field rotation velocity was chosen to be slow enough to ensure comparable magnitudes of TEMC and electromagnetic stirring. It is experimentally demonstrated that such an interaction refines the grain spacing and homogenizes the material structure. Sn-10%wt.Pb alloy was used as a test alloy to qualitatively verify the relationship of the grain spacing and magnetic field rotation velocity and the strength and solidification velocity.