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Introduction. Transverse vibrations of a bimorph consisting of two piezomagnetoelectric layers and located in the alternating magnetic field are investigated. Piezomagnetoelectric layers are multilayer composites with alternating piezoelectric and piezomagnetic layers. The mechanical and physical properties of such a composite are given by known effective constants.Materials and Methods. The applied theory of multilayer plate vibrations takes into account the nonlinear distribution of electric and magnetic potential in piezoactive layers in the longitudinal and transverse directions. On the basis of this theory, the stress-strain state, the dependences of deflection, electric and magnetic potentials on the volume ratio of the composition of the hinged bimorph, are investigated. The electric potential is assumed to be zero at all electrodes, while the magnetic potential is zero at the inner boundary and unknown at the outer boundaries. Therefore, the distribution of electric and magnetic potentials in the middle of the layer are unknown functions. In the case of the magnetic potential, the distribution at the outer boundary is also unknown. In the problem, the Kirchhoff hypotheses for mechanical characteristics were accepted. The use of the variational principle and the quadratic dependence of the electric and magnetic potentials on the thickness of piezoactive layers made it possible to obtain a system of differential equations and boundary conditions.Results. When the volume ratio of the composition of piezoactive bimorph materials changes, the electric potential in the middle of the layer changes nonlinearly. The magnetic potential in the middle of the layer and at the outer boundary increases almost linearly with an increase in the volume percentage of BaTiO3. The dependence of the deflection in the middle of the layer is determined.Discussion and Conclusions. An applied theory for calculating transverse vibrations of a bimorph with two piezomagnetoelectric layers is constructed. The dependence of the characteristics of the stress-strain state, electric and magnetic fields on the volume fractions of piezomagnetic and piezoelectric materials, is investigated.

Introduction. Transverse axisymmetric oscillations of a bimorph with two piezo-active layers, piezoelectric and piezomagnetic, are studied. This element can be applied in an energy storage device which is in an alternating magnetic field. The work objective is to study the dependence of resonance and antiresonance frequencies, and electromechanical coupling factor, on the geometric parameters of the element.Materials and Methods. A mathematical model of the piezoelement action is a boundary value problem of linear magneto-electro-elasticity. The element consists of three layers: two piezo-active layers (PZT-4 and CoFe2O4) and a centre dead layer made of steel. The finite element method implemented in the ANSYS package is used as a method for solving a boundary value problem.Results. A finite element model of a piezoelement in the ANSYS package is developed. Problems of determining the natural frequencies of resonance and antiresonance are solved. Graphic dependences of these frequencies and the electromechanical coupling factor on the device geometrics, the thickness and radius of the piezo-active layers, are constructed.Discussion and Conclusions. The results obtained can be used under designing the working element of the energy storage device due to the action of an alternating magnetic field. The constructed dependences of the eigenfrequencies of the resonance and antiresonance on the geometric parameters of the piezoelement provide selecting the sizes of the piezo-active layers for a given working frequency with the highest electromechanical coupling factor.