The effect of an electric current on rod-eutectic solidification in Sn-0.9 wt.% Cu alloys

A directionally solidified Sn-0.9 wt.% Cu rod eutectic alloy is subject to sustained electrical current pulses applied parallel to the direction of growth. The current pulses result in disruption of the aligned rod morphology giving rise instead to segments of the rod (Cu6Sn5) phase embedded in the Sn matrix. A model for the directional growth of the eutectic in the presence of an electric current is presented. The model is used to illustrate that electromigration is unimportant in affecting changes in spacings for steady eutectic growth conditions.