Surface/interface effect on the propagation of high-frequency SH surface waves in an ultra-thin FGP over-layer bonded to a substrate

Autor: Hossein M. Shodja, C. Enzevaee
Rok vydání: 2021
Předmět:
Zdroj: Acta Mechanica. 232:4677-4689
ISSN: 1619-6937
0001-5970
DOI: 10.1007/s00707-021-03077-3
Popis: Shear horizontal surface acoustic waves (SAW) propagation in an ultra-thin functionally graded piezoelectric (FGP) layer bonded to a homogeneous substrate is analytically formulated in the mathematical framework of surface/interface elasticity theory. It is assumed that the FGP over-layer is made of a hexagonal 6-mm crystal with a single axis of rotational symmetry coinciding with the axis of polarization. The mechanical and piezoelectric properties of the layer are assumed to vary linearly with thickness. The half-space is made of a transversely isotropic material. It should be mentioned that this model is of great interest in investigating SAW devices at high frequencies. Accounting for the surface/interface effects, the pertinent electromechanical dispersion relation for both cases of the electrically open and short surfaces is derived analytically using Wentzel–Kramers–Brillouin singular perturbation theory. The effects of the surface/interface parameters and the gradient parameter which indicate the variation of the piezoelectric properties of the FGP layer on the dispersion relation, the electromechanical coupling factor, displacement field, electric potential function, electric displacement field, and stress field are studied numerically, and the results are compared with those obtained from classical theory.
Databáze: OpenAIRE