Vibration And Finite Element Analysis Of Magnetoelectric Layered Structure

The laminate composites have high magnetoelectric voltage coefficients，used in themagnetic field detection, energy conversion of the electromagnetic field,sensors, etc. It hasbecome a hot issue in this field in recent years. This thesis investigates the vibration andmagnetoelectric voltage coefficients of the laminate laminated composites by means of finiteelement method. The measure system of the magnetoelectric effect is established, and themagnetoelectric voltage coefficients are obtained.1. The PDE module of the finite element software COMSOL is used to analyze the magneto-electric effects of the magnetoelectric layered plate and the cantilever structure, respectively. Thefinite element model of the magneto-electric laminate composites is established by inputtingconstitutive relation, meshing solid model, applying loads and boundary conditions. We can obtainthe resonant frequency and the magneto-electric voltage coefficients of the laminate composite byPDE modules. The effects of a biasing magnetic field on magneto-electric coupling coefficient arestudied and discussed.2．Furthermore, we design and build the testing platform of magneto-electric effects, and testthe magneto-electric effect of the Terfenol-D/PZT/Terfenol-D specimen by means of the platform.From the experiment results, we can find that the ME coefficient in the resonance frequency stationis higher than that in the low-frequency station. The resonance frequency of the ME specimendecreases with increase of the biasing magnetic field first till achieving the lowest value, and thenincreases. ME coefficient increases rapidly with increasing basing magnetic field, and thendecreases. From the results of the experiment and the finite element analysis, we can find thetendency of both is similar.3. The propagation of Rayleigh wave under a biasing magnetic field is investigated for apiezomagnetic layer on a piezoelectric half space structure. The dispersion curves are presented forfour kinds of boundary conditions. We can find that the phase velocity is sensitive to the biasingelectric field, and the displacement and stress fields can be affected by the biasing electric field.The analytical method and the results can be useful for the design of the resonators and sensors.