Detection of defects in aerostructures using non-contact ultrasonic transducers

Abstract

This paper describes an investigation into the possibility of using non-contact ultrasonic transducers for detecting defects in aerostructures. Our study deals with an ultrasonic method that underscores the recent advances in non-contact and anlytical methodologies. Ultrasonic waves are generated by a transducer connected to a Sonatest DryScan 410D using through-transmission mode. In this investigation, ultrasonic through-transmission signals passing through the aerostructures are analyzed with respect to their amplitudes. We treat this problem experimentally. Various aspects of our approach are presented. The observations reported in this paper deal with defects in aluminium, composite and re-inforced plastic with wood layer structures. Results obtained using non-contact ultrasonic sensors are compared with those obtained by using the Eddy current testing method. The results obtained by both methods are in good agreement, indicating that these techniques can be considered as quantitative nondestructive tools for detecting defects in aerostructures. Results are presented and discussed. © 2013 Acoustical Society of America.