A new design and manufacturing process for embedded Lamb waves interdigital transducers based on piezopolymer film

• Published in: Sensors and actuators. A. Physical. Vol. 123; pp. 379 - 387
• Main Authors: Bellan, Filippo, Bulletti, Andrea, Capineri, Lorenzo, Masotti, Leonardo, Yaralioglu, Goksen G., Degertekin, F. Levent, Khuri-Yakub, B.T., Guasti, Francesco, Rosi, Edgardo
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 23.09.2005
• Subjects: Carbon fiber composites; Carbon fiber reinforced plastics; Electrodes; Interdigital transducers; Lamb waves; Laminates; Mathematical analysis; Non-destructive testing (NDT); Polyvinylidene fluoride (PVDF); Polyvinylidene fluorides; Smart materials; Transducers; Lamb waves; Polyvinylidene fluoride (PVDF); Non-destructive testing (NDT); Interdigital transducers; Carbon fiber composites; Smart materials
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2005.05.013

In this work a new technology for designing and manufacturing ultrasonic interdigital transducers (IDT) is presented. The piezoelectric material used is a metallised piezopolymer film made of polyvinylidene fluoride (PVDF) with electrode pattern obtained with a laser ablation process. Piezopolymer transducer prototypes are designed with wavelength of 8 mm to operate with Lamb waves (symmetrical S 0 mode). An experimental validation of the piezopolymer IDT design is demonstrated with a transmitter-receiver IDT pair embedded in a 3 mm thick carbon fiber reinforced plastic (CFRP) composite laminate. Acoustical response and the electrical impedance have been calculated. These transducers are proposed for monitoring structural integrity of structures/components made of carbon epoxy composite laminates commonly used in spacecrafts, satellite and airplanes.