Dynamic Magnetoelectric Effect of Soft Layered Composites with a Magnetic Elastomer

Abstract

Multilayered magnetoelectric materials are of great interest for investigations due to their unique tuneable properties and giant values of magnetoelectric effect. The flexible layered structures consisting of soft components can reveal lower values of the resonant frequency for the dynamic magnetoelectric effect appearing in bending deformation mode. The double-layered structure based on the piezoelectric polymer polyvinylidene fluoride and a magnetoactive elastomer (MAE) with carbonyl iron particles in a cantilever configuration was investigated in this work. The gradient AC magnetic field was applied to the structure, causing the bending of the sample due to the attraction acting on the magnetic component. The resonant enhancement of the magnetoelectric effect was observed. The main resonant frequency for the samples depended on the MAE properties, namely, their thickness and concentration of iron particles, and was 156–163 Hz for a 0.3 mm MAE layer and 50–72 Hz for a 3 mm MAE layer; the resonant frequency depended on bias DC magnetic field as well. The results obtained can extend the application area of these devices for energy harvesting.

Low-Frequency Resonant Magnetoelectric Effect in a Piezopolymer-Magnetoactive Elastomer Layered Structure at Different Magnetization Geometries

“…Similar results were obtained in another work [29]. It should be also noted that the generation of ME voltage harmonics can also be suggested [33]. In another work [32], measurements of the ME effect were carried out in a uniform magnetic field directed in the plane of the structure (so-called L-T geometry).…”

“…Resonance enhancement of the ME effect was also observed [32,33]. In a work [33], it was shown that the resonance frequency in the T-T configuration in the AC gradient magnetic field for the first resonance mode decreases with the increasing magnetic field. Similar results were obtained in another work [29].…”

“…The MAE layer is stretched in the direction of the bias field due to the magnetodeformation effect. Namely, the particles in the MAE layer displace the elastic matrix in a homogeneous field, as opposed to gradient excitation [33]. The MAE layer was bonded to the substrate, so its stretching, or magnetodeformation, caused it to pull the more elastically hard piezopolymer layer behind it, causing bending.…”

“…The magnitude of the ME coefficient in geometry 2 exceeds that of geometry 1, which is due to the greater magnitude of the sample deflection in the magnetic field. Table 1 summarizes the previously obtained results in different composite structures based on MAE [30][31][32][33] for comparison. It can be seen that the obtained value of ά1 ≈ 1.8 V/(cm•Oe) at magnetization along the long side (geometry L-T) is smaller than that previously obtained for composite structures, which may be due to the non-optimal thickness of the MAE layer [32].…”

“…A two-layered structure composed of PVDF and magnetic elastomer was investigated earlier [29][30][31][32][33]. The initial experiments of the magnetoelectric effect were carried out in a pulsed magnetic field of different forms oriented transversally [29][30][31].…”