NDT Application of Air-Coupled Ultrasonic Transducer For Honeycomb Composite

Utilizing the 1-3 piezoelectric composite and double-layer matching structure, the study discusses the research of piezoelectric air-coupled transducer from multi-layer parallel structure. The multi-layer parallel structure owns the benefits of better electrical impedance and larger piezoelectric strain constant and the experimental outcomes verify that it is effective to perfect the performance of piezoelectric air-coupled transducer. According to above research, this paper also presents a seven-element auto-focused air-coupled transducer. In the end, the internal defects of honeycomb composite are measured utilizing the seven-element auto-focused air-coupled transducer under pitch-catch mode.