Ultrasonic lamb waves in layered piezoelectric plates

摘要

The propagation of guided ultrasonic waves (GUW) in deformable solid media has been an active research subject for the last thirty years due to its applications in non-destructive evaluation (NDE) of homogeneous and advanced composite materials used in mechanical, aerospace and civil engineering [1-4]. Stratified and fibrous piezoelectric composite materials have also lately given rise to increasingly active researches because of its numerous possible applications in sensors, actuators, active control and adaptive structures for their electromechanical conversion abilities [5]. Recently, the microelectronic technology has outstandingly progressed, particularly in the domain of multilayered piezoelectric semiconductors structures: heterostructures, multiple quantum well structures and the monolithic integration of surface acoustic waves (SAW) devices [6]. The high-performance electro-acoustic and acousto-optic devices utilizing GUW in multilayered structures are currently developed for a variety of applications in the field of communications, signal processing, optical computing. Thus, a detailed knowledge of the GUW propagation characteristics in piezoelectric multilayered structures, crucial for the accurate design of GUW devices, is urgently required. However, the task complexity due to great variety of structure geometries and related type of wave delay advances. Modeling wave propagation in piezoelectric layered media must take into account electromechanical material properties of layers, number and thickness of layers, electromechanical nature of interfacial and boundary conditions, and direction of propagation as well. Limited available analytical treatments make them fully dependent on computational capabilities. Also attempts in modeling ultrasonic waves propagation reported in literature can hardly cope with the demands of results in a large range of frequency along with a simple fast method.