Growth of Fe-Ga Alloy Single Crystals by the Czochralski Method and Their Application to Vibration Power Generator

An Fe-Ga alloy single crystal of about 10 mm in diameter and about 60 mm in length was grown by the Czochralski (CZ) method. The as-grown ingot was approximately oriented in the 〈100〉 direction parallel to the pull-up direction. The gallium concentration of the as-grown ingot was close to that of the starting polycrystalline alloy. The magnetostriction of about -212 ppm was observed in the 〈100〉 direction by applying a magnetic field perpendicular to the measured direction. In addition, the superior performance of vibration power generation due to the large inverse magnetostrictive effect was demonstrated by a prototype device using the as-grown Fe-Ga alloy single crystal. It is concluded that Fe-Ga alloy single crystals grown by the CZ method are promising for application to vibration power generators.