Detection of delaminations in non-metallic materials using guided acousto-ultrasonics


5th National Conference on NDT of the Hellenic Society of NDT (HSNT), 18-19 November 2005, National Technical University of Athens.

Konstantinos Bollas, Dimitrios Kouroussis, George Chryssos, Athanasios Anastasopoulos


The paper reports the application of non-destructive testing techniques for the quality control of wooden or limestone structures. Wooden and limestone samples with one or two layers, containing artificial imperfections (delaminations), were tested using Ultrasonics, Sondicator and Acousto-ultrasonics. In order to improve the resolution and the sensitivity of delamination detection, the method of acousto-ultrasonics was modified using special designed waveguides and excitation using arbitrary waveform generation. The present work summarizes the basic principles of this new method, named Guided Acousto Ultrasonics (GAU), its application and procedure for delamination detection. In addition to that, the present work describes, the other NDT methods used and the respective inspection results. Finally comparison is made between the different NDT methods used and discussion is held on the possibility of delamination mapping in wood or limestone for depths up to 0.5cm.