Refinement of solidified structure using DC electromagnetic field

Abstract

The Sn-10%Pb alloy has been solidified under the imposition of a direct current and a static magnetic field perpendicular each other for the excitation of an electromagnetic force in the local region of the sample to clarify the effect of operating parameters on the solidified structure. The electromagnetic force induced by the simultaneous imposition of the direct current and the static magnetic field does not excite the nucleation in this investigation. And the solidified structures obtained under the different intensities of the direct current and the static magnetic field are compared each other for optimization of the electromagnetic field in this process. Increase In the direct current is preferable for the refined structure formation under the constant magnetic field intensity. Under the constant product of the direct current and the static magnetic field, refining effect of the solidified structure is the same level under the certain value of the magnetic field. Over this critical magnetic field, the refining effect decreases because the melt flow caused by the imposed electromagnetic force is suppressed by the interaction between the magnetic field and the fluid motion. © 2008 ISIJ.