The effect of interfacial geometry on magnetoelectric composites performance
Developing new technology based smart magnetoelectric (ME) composites, will allow designing antennas several orders of magnitude smaller, with higher efficiency, while working in lower frequencies. The two-phase ME composite consists of a piezoelectric and magnetostrictive phases. ME composite devices convert magnetic energy to electrical energy through a two-step process: magnetic energy is first converted to mechanical energy via magnetostriction in the magnetic part of the ME composite, and then the mechanical energy is converted to electrical energy via the piezoelectric component through strain coupling.
The ME device performance is majorly determined by: Material properties, structure and geometry1, Phase connectivity. For example, a simple geometry can be a laminate structure: 2 films (or more) connected at their faces. Alternatively, the composite topology can take different forms, such as array of thin magnetic rods or spheres embedded within a piezoelectric bulk. In the case of rods, and other geometry variations, the surface area in the interface, between the 2 phases, increases. In our study, we examine if this increase leads to improved ME coupling, as the coupling is mediated by mechanical strain through the interface between the 2 phases.
We studied the effects of ME composites interfacial geometry on the ME coupling, by performing simulations in COMSOL. COMSOL is a leading finite element simulation software, with a strength in multi-physics problem solving – such as that of a magnetoelectric antenna. The simulated structure consisted of a 2 layers composite: AlN as a piezoelectric and Terfenol-D as the magnetostrictive, with dimensions in the mm range. The composite’s performance, on and off resonance, were studied as a function of the micro-scale features of the interface.
1. He, Yifan, Bin Luo, and Nian-Xiang Sun. "Integrated magnetics and magnetoelectrics for sensing, power, RF, and microwave electronics." IEEE Journal of Microwaves (2021).
Powered by Eventact EMS