Air-coupled ultrasonic non-destructive testing of aerospace components

Abstract

Two different single-side air-coupled ultrasonic techniques for detection and visualisation of defects in aerospace composite materials are presented in this paper. The first technique is based on the pitch-catch arrangement of the transducers and application of the Lamb wave which is shielded by defects. The second method, which gives more accurate results of defect geometry estimation, is based on the same orientation of the transmitter and the receiver for reception of the Lamb wave scattered-reflected by the defect. The damage visualisation results of both techniques are investigated. The results of in situ damage detection are presented. The possibilities of the air-coupled ultrasonic technique for the rapid detection of defects in composite materials are investigated.