Abstract
Giant magnetostrictive materials have been used for actuators and sensors. The materials show hysteresis loss when compressive load is applied and removed, and the hysteresis properties vary with magnetic field. This characteristics can be used as a energy/vibration absorber. This report deals with the damping properties of the giant magnetostrictive materials fabricated by the powder metallurgy process and effects of the stress intensity and the bias magnetic field on the damping properties. This material showed hysteresis clearly with the stress smaller than 30MPa. The magnetostriction which causes the energy absorption during loading/unloading of the stress, was generated in low stress. With stress larger than 50MPa, the magnetostriction saturated and did not affect the damping property. The bias magnetic field increased the magnetostriction induced by the compressive stress and reduced the residual strain and Young's modulus.
