2007 Volume 47 Issue 11 Pages 1613-1617
For optimization of alternating current imposing period in the crystal alignment process in which both a static magnetic field and an alternating current are imposed on an alloy during solidification, experimental work has been done using a Sn–10mass%Pb alloy. Index of crystal alignment decreases with increase in the imposing period of the alternating current because the electromagnetic torque induced in the sample disturbs the alignment of solid particles suspended in the liquid phase. Electromagnetic torque is dominant as resistance of the crystal rotation to magnetically preferred direction when the size of the crystal is 21 μm or larger. For the optimization of the crystal alignment in this process, imposing period of the electric current and the magnetic field should be controlled as follows. The electric current and the magnetic field are simultaneously imposed on the alloy only in the initial stage of the solidification. Then the electric current is turned off and only the magnetic field is imposed during the solidification.