International Journal of Aerospace and Lightweight Structures (IJALS)Volume 3 Number 1 (2013)
An Attenuation Baseline of Guided Waves for Debonding Detection in Sandwich Composite Structures
Mechanical and Mechatronic Engineering, the University of Sydney, NSW 2006, Australia.
In this study, the characteristics of wave signals (leaky or non-leaky) attenuated by debonding in sandwich CF/EP composite panels were investigated. A baseline of wave attenuation was constructed to define a damage signature. An algorithm to detect debonding and damage in sandwich CF/EP composite plates using guided waves was developed, based on the instantaneous baseline wave attenuation of individual wave signals actuated and captured by PZT actuators and sensors. The fundamental symmetric S0 mode and anti-symmetric A0 were excited using circular PZT elements mounted on the surface of the plate, and their ability to detect debonding and damage in sandwich CF/EP composite plates was evaluated. The algorithm eliminates the need for benchmark data from the intact state structure. The results demonstrate the effectiveness of the method in identifying debonding as well as damage located in different positions in the sandwich composite structures.
Keywords: Damage signature, Debonding, Guided waves, Leaky/non-leaky, PZT, Sand- wich CF/EP composite.