Propagation of shear horizontal surface waves in a layered piezoelectric half-space with an imperfect interface
ABSTRACT We investigate the dispersive behavior of shear horizontal (SH) surface waves propagating in a layered structure consisting of a piezoelectric layer and an elastic half-space, in which the top and bottom of the layer are electrically shorted. The interface between the layer and the half-space is assumed to be imperfect bonding. The degree of imperfection of the interface is described by the so-called shear-lag model. The dispersion equations are expressed in an explicit closed form. The phase velocities are calculated to show the influences of the interfacial imperfection and the material properties of piezoelectric layers on the dispersive characteristics.
- SourceAvailable from: Feng Jin[Show abstract] [Hide abstract]
ABSTRACT: The effect of functional graded piezoelectric materials on the propagation of thickness-twist waves is investigated through equations of the linear theory of piezoelectricity. The elastic and piezoelectric coefficients, dielectric permittivity, and mass density are assumed to change in a linear form but with different graded parameters along the wave propagation direction. We employ the power-series technique to solve the governing differential equations with variable coefficients attributed to the different graded parameters and prove the correction and convergence of this method. As a special case, the functional graded middle layer resulting from piezoelectric damage and material bonding is investigated. Piezoelectric damaged material can facilitate energy trapping, which is impossible in perfect materials. The increase in the damaged length and the reduction in the piezoelectric coefficient decrease the resonance frequency but increase the number of modes. Higher modes of thickness-twist waves appear periodically along the damaged length. Moreover, the displacement of the center of the damaged portion is neither symmetric nor anti-symmetric, unlike the non-graded plate. The conclusions are theoretically and practically significant for wave devices.Smart Materials and Structures 08/2013; 22(9):095021. · 2.45 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Bleustein–Gulyaev (B–G) waves in a functionally graded transversely isotropic electro-magneto-elastic half-space, in which all parameters exponentially change along the depth direction, are investigated, and the dispersion equations with respect to the phase velocity for electromagnetically open and shorted conditions are obtained. The B–G waves are dispersive because of the inhomogeneity of the material, which is different from a pure substrate. The graded coefficient exhibits different effects on the B–G waves at different electromagnetic circumstances. With the intervention of the functionally graded material, the electro-magneto-mechanical coupling factor can be improved and the penetration depth of the B–G waves can be decreased. The results can be used in the design of high-performance surface acoustic wave devices.European Journal of Mechanics - A/Solids 01/2013; 37:17–23. · 1.90 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: We analytically investigate shear horizontal surface acoustic wave (SH-SAW) propagation in layered piezoelectric structures loaded with viscous liquid, which involves a thin piezoelectric layer imperfectly bonded to an unbounded elastic substrate. The coupling wave equations are obtained based on the linear piezoelectric theory. The governing equations are solved by means of the analytical method with consideration of electrically open and shorted cases, respectively. The dispersive relations are obtained, and the effects of the imperfect constant on the properties of waves are presented and discussed. From the numerical results, we can find that the phase velocity decreases with the increase of the interface parameter n, and for a specified viscosity, the attenuation increases with the interface parameter. The results show that the effects of the imperfect constant on the properties of SH-SAW are remarkable.Acta Mechanica 01/2014; · 1.27 Impact Factor