Low frequency bending piezoelectric actuator with integrated ultrasonic NDE functionality

• Published in: NDT & E international : independent nondestructive testing and evaluation Vol. 38; no. 8; pp. 627 - 633
• Main Authors: Gex, Dominique, Berthelot, Yves H., Lynch, Christopher S.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.2005; Elsevier Science
• Subjects: Acoustical measurements and instrumentation; Acoustics; Composite bending actuators; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Materials science; Materials testing; Measurement and testing methods; Physics; Solid mechanics; Structural and continuum mechanics; Ultrasonic NDE; Ultrasonic piezoelectric waveguides; Ultrasonic piezoelectric waveguides; Ultrasonic NDE; Composite bending actuators; Acoustic measurement; Piezoelectric sensor; Segmentation; Unidirectional fiber material; Epoxy resin; Thick plate; PZT; Low frequency; Piezoelectric ceramics; Fatigue test; Pitch catch testing; Ultrasonic control; Piezoelectric actuators; Metrology; Aramid fiber; Fiber orientation; Embedded transducer; Non destructive test; Residual stress; Electromechanical properties
• ISSN: 0963-8695; 1879-1174
• DOI: 10.1016/j.ndteint.2005.02.012

A bending piezoelectric actuator has been manufactured with a 250 μm thick PZT plate embedded in five layers of unidirectional fiber Kevlar epoxy. The selected orientation of the fibers produces a gradient of residual stresses in the composite that enhances bending actuation. By segmenting the electrodes, it is possible to launch an ultrasonic pulse in the actuator so that structural health monitoring of the actuator itself can be performed using pitch catch ultrasonic NDE during the low frequency actuation. Qualitative experimental results of fatigue tests and damage detection are presented.