2009 Volume 50 Issue 3 Pages 461-466
Giant magnetostrictive Fe-Pd and Fe-Ga alloys are promising as actuator/sensor materials with high respective velocity and stress created by magnetostriction. To apply them to a micro-gas valve, we developed magnetostrictive actuators, that is, Fe80Ga20/Ni and Fe70.4Pd29.6/Ni bimorph layers. These cantilever-type actuators can be bent by applying magnetic field parallel to length. An actuator point displaced about 300 μm under a low magnetic field of 37 kAm−1. Small and large actuators were applied to a micro-gas valve. The opening and closing action of a gas valve consisting of magnetostrictive bimorph layers can be controlled remotely by magnetic fields. Gas flow rate can be driven from 50 to 0 mL·min−1 by increasing the magnetic field to 40 kAm−1. The response time to the applied magnetic field is below 0.15 s.