Magnetic field enhanced phase precipitation in an undercooled Co-Sn alloy

The primary phase growth in undercooled Co₇₆Sn₂₄ hypoeutectic alloy without and within magnetic field has been studied. Results show that the critical undercooling for the precipitation of primary αCo dendrite phase is strongly affected by the external magnetic field. With the increasing magnetic field intensity, the critical undercooling for the disappearance of primary αCo dendrite phase will be increased from 25 K without magnetic field to more than 100 K with 12 T magnetic field. The variation of the critical undercooling is discussed based on the enhanced growth velocity of primary αCo dendrites caused by the increased curvature undercooling due to the demagnetizing effect in high magnetic field.