Shape Memory Effect in Fe-Pd Magnetic Shape Memory Alloy Thin Films

Abstract

The shape memory effect (SME) and magnetic shape memory effect (MSME) in Fe-Pd thin film were studied using the film curvature method. The residual stress changes due to the SME and MSME in Fe-Pd film were measured during thermal cycling and magnetic field changing, respectively. A Fe-Pd thin film with a lateral composition gradient was deposited onto the micromachined 7x7 cantilever beam array substrate, such that each of the cantilever beams was coated with a film of different composition. There was an abrupt stress change in only the 28.1 at % Pd thin film as the temperature of the film was cycled, and the corresponding stress change was measured as 0.16 GPa. The film with 29.4 at % Pd showed the abrupt stress change under a magnetic field of 0.7 Tesla, which means that the film of the composition had the MSME.