Effect of an axial high magnetic field on the microstructure in directionally solidified Pb-Sn eutectic alloy

The effect of a high magnetic field on Pb-Sn lamellar eutectic growth has been investigated experimentally during the directional solidification process. It has been found that the magnetic field has caused the occurrence of the morphological instability of the lamellar eutectic. Indeed, the magnetic field has deflected the eutectic lamellae from the solidification direction, and with an increase of magnetic field intensity and decrease of growth speed, the deflection angle increases. Along with the deflection of the eutectic lamellae, the lamellae become oscillatory and segregation takes place. Discussion of the above experimental results focuses on the alignment and spiral growth of the eutectic lamellae under a high magnetic field.