Strong Magnetic Field Effect on Surface Tension Associated with an Interfacial Magnetic Pressure

The surface tension/interfacial energy is found to be influenced by a strong magnetic field. This phenomenon is associated with an increase in the anomalous morphology of the eutectic during solidification of a hypereutectic Al-Cu alloy in strong magnetic fields. On the basis of further in situ differential thermal analyses, this increase is related to additional undercooling provoked by the magnetic field. A semiquantitative model is developed to reveal the underlying mechanisms. It is proposed that the heterogeneous nucleation is hindered through an increase in contact angle between the liquid and the crucible as a result of an additional surface tension, which is induced by the interfacial magnetic pressure. By revealing this effect, the present model can also clarify the contradictory phenomenon for liquid bismuth in literature.