Reexaminations of the effects of magnetic field on the nucleation of undercooled Cu melt

The effect of a high static magnetic field on the nucleation of an undercooled Cu melt has been investigated using a glass slag fluxing technique in a 12 Tsuperconductor magnet. Controlled heating cycles with and without a magnetic field are performed and the results indicate that the magnetic field has no single effect on the mean undercooling of undercooled Cu liquid, which is different from previous reports. The high static magnetic field can enhance the undercooling of Cu at first, and the effect is weakened with increasing number of heating cycles. The undercooling of undercooled Cu is saturated at around 250K regardless of the magnetic field after a certain number of heating cycles. The effects are interpreted on the basis of the thermodynamic and magnetohydrodynamic effects of the magnetic field on the undercooled melt and the heterogeneous nucleation theory.