Abstract：This paper investigates shear horizontal (SH ) waves propagating in a sandwich structure consisting of a piezoelectric layer and two different functionally graded piezoelectric half-spaces. The material properties of the piezoelectric half-spaces vary exponentially in the direction perpendicular to the interfaces. The closed-form expressions of electro-elastic fields for SH waves are derived. By using the continuous conditions at the interfaces, the dispersion equations are given in determinant form. Based on the dispersion equations, the numerical examples are presented to show the effects of variations of material properties, piezoelectric layer thickness and different combinations of materials on the phase velocity. The obtained results are useful for the application of functionally graded piezoelectric materials to acoustic wave devices such as plate resonators, filters and sensors.
2012, Vol. 33 
