DETECTION OF DISBONDING IN GLARE COMPOSITES USING LAMB WAVE APPROACH

Lamb‐waves can be used to detect disbonds in composite plates. In this work, a photoacoustic technique was first applied to measure the dispersive property of a GLAss‐REinforced (GLARE) composite panel. The measured phase velocity dispersion curves are consistent with the theoretical calculation using the classical transfer matrix method for layered media. Based on the obtained properties, a finite element method (FEM) model was constructed to study the influence of a disbond void on the Lamb wave propagation in the GLARE plate. It is found that the displacement amplitudes of the $Ao$ mode Lamb wave decrease while its travel time increases as the disbond size increases.