The propagation behavior of Love waves in a functionally graded layered piezoelectric structure

• Published in: Smart materials and structures Vol. 14; no. 1; pp. 137 - 146
• Main Authors: Liu, J, Wang, Z K
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.02.2005; Institute of Physics
• Subjects: Exact sciences and technology; Fundamental areas of phenomenology (including applications); General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Measurement and testing methods; Physics; Servo and control equipment; robots; Solid mechanics; Structural and continuum mechanics; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Acoustic wave device; Cut off frequency; Phase velocity; WKB approximation; Deformation modulus; Functionnally graded material; Coupled modes; Surface wave; Free surface; Vibrational mode; Permittivity; Elastic foundations
• ISSN: 0964-1726; 1361-665X
• DOI: 10.1088/0964-1726/14/1/013

The propagation behavior of Love waves in a functionally graded layered piezoelectric structure is investigated in this paper. It involves a thin piezoelectric layer, in which the parameters vary linearly in the thickness direction, bonded perfectly to an elastic substrate. By the WKB method, the phase velocity equations are obtained for both electrical open and short cases on the free surface, respectively. The results show that the circular frequency and cut-off frequency increase as the elastic modulus and dielectric constant vary linearly respectively; meanwhile, the number of vibration modes decreases, and the coupled electromechanical factor increases with the decrease of the dielectric constant. Undoubtedly, this is useful for the design of surface acoustic wave (SAW) devices.