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Magnetoelectric effect (ME), with its significant application value drawing widely attention instorage, sensors, energy harvester and so on, is the hot issue of research in the world. Themagnet/piezoelectric composite’s giant magnetoelectric effect is made of the magnetic torque effectand piezoelectric effect combination, named magnetoleltric torque effect (MET).Themagnetoelectric torque device, which is different from tradational ME film devices with outmagnetostraction materials, has the advantages of simple structure, low price and bigmagnetoelectric coefficient, low resonance point, low frequency test features. So it couldeffectively detect electromagnetic field signal and the realize magnetoelectricity conversion ofenergy.At first, magnetic torque device of magnet/piezoelectric composite’s coupling field theory hasbeen carried on the preliminary study, finite element analysis research, the basic principle ofmagnetic torque electric is elaborated; And design and manufacture the test system andexperimental equipment, set up a regular magnetic torque electric test platform and threedimensional space magnetoelectric effect test platform; For the magnetic components of spaceinformation data, cooperated with the theoretical analysis, obtained the best induction deviceorientation, and draw the3-D response figure.The low frequency property of MET has been investigated. Using theoreticalanalysis and finite element simulation method, based on elastic mechanics, electricitydynamics, piezoelectric theory, the magnet/piezoelectric composite analysis ofphysical model is constructs. In view of the magnetoelectric properties of quasi static,established equation and derived device magnetoelectricity output equation, clear anddefinite the relations on magnetoelectric device length, thickness, material ofremanent magnetism, piezoelectric constant, dielectric constant, the elastic constants,external applied magnetic field and so on. The research also discusses the mainfactors affecting device magnetoelectricity effect, for the samples of NdFeB/PZTcomposite structure, the magnetoelectric device of the quasi static experiments havebeen carried out to verify the theoretical output equation. The dynamic response of MET has been investigated.Using vibration partialdifferential motion equation of the plate, the dynamic response of the MET model is established.According to the mechanical and electrical magnetic torque electric boundary conditions, dynamicmagnetoelectric response value is deduced, which has been clear the relationships the resonancefrequency with the device length and quality of the tip mass loading; And design the correspondingexperiment, for example NdFeB/PZT composite structure, the experiments have been carried outto verify the output equation of magnetoelectric devices; Further more, the derivative model ofMET structure has been studied, including the Multi-coupling magnetoeletric (MEM) structure andadd more flexible substrate structure, which has preliminary achieved the response value ofmagnetoelectric properties with the structure relationship.
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