AC field induced rotation of magnetostrictive nickel wires

AC field induced rotation is here reported in polycrystalline nickel wires after its discovery few years ago in amorphous wires. The dependence with b oth frequency and amplitude of AC exciting magnetic field has been measured for wires with different diameters. The results suggest that the phenomeno n is general in magnetostrictive materials and not only related to amorphou s wires. Additionally the contribution of the eddy currents to this effect is suggested from the dependence of the rotation frequency with the excitin g field frequency.