Demonstration of Hybrid Mechanism:
FePd and Fe cantilever beams under applied magnetic field

A cantilever beam made by polycrystalline FePd is simultaneously actuated with a ferromagnetic Fe beam by a portable electromagnet. Both beams have the same geometry. It is clearly demonstrated that the Fe-Pd beam has much larger deflection than the Fe one. It is mainly due to the hybrid mechanism (austenite à martensite phase transformation). Note that magnetization of FePd in austenite is similar to the one of Fe. Furthermore, since the ratio of the Young's modulus of Fe (210GPa) to Fe-Pd (80GPa in austenite phase, 30GPa in martensite phase) is about 3 ~ 7 range, the ratios of the bending deflection of Fe-Pd to Fe could be also 3 ~ 7. However, the demonstration results shows the tip of Fe-Pd beam exhibits 7 mm displacement during the application of the magnetic field, while the Fe beam shows almost no deflection. As the gape between the specimen and the electromagnet becomes smaller during the deformation, the larger magnetic force, leading to more phase change. This comparison result shows that the Fe-Pd FSMA as an actuator material is superior to the conventional material. Both cantilever beams spring back to the original position when the electromagnet turns off.