DEFECT DETECTION IN BONDED STRUCTURES USING THE REVERBERANT WAVEFIELD

摘要

This paper has presented a new approach for imaging defects in bonded structures using multiply-scattered acoustic waves. The approach uses a simple sensitivity kernel description to describe the wavefield within the structure. All waves including multiply-scattered and boundary related waves are implicitly included in the formulation. The bondline stiffnesses are obtained by binary inversion of the wavefield recorded at multiple receivers and frequencies using an empirical sensitivity kernel. The primary advantage of this method is that it uses the entire wavefield including multiply scattered waves and only a limited number of measurements to image parts of the bond which contain defects. Future work will focus on determining the optimum receiver configurations and frequencies for flaw detection and the application of the method to adhesive-bonded plate structures.