Published online by Cambridge University Press: 01 February 2011
The giant magnetostrictive films exhibit promising device applications for micro-machines and sensor systems due to high response velocity and huge stress created by the magnetostriction. We developed magnetostrictive bimorph-type Fe70Pd30 or Fe83Ga17 (positive magnetostriction)/Al/Ni(negative magnetostriction) thin films by magnetron sputtering. Magnetostriction of these films measured by a bending cantilever beam method has reached 250–300 ppm in the small magnetic field of 1.0 kOe and exhibits little hysteresis. Moreover, the magnetostrictive characteristics do not change under low alternating magnetic field. The magnetoelastic coefficient of these films is 25∼30 MPa, which is comparable to the coefficient of the PbTiO3-PbZrO3 system. These metallic sensor/actuator materials are useful for applications in magnetostrictive 2D- scanners and remote-interrogated tire sensors.