Damage Detection in a Multi-Layered, Multi-Material Composite Using Air-Coupled Ultrasonic Resonance Imaging

Air-coupled ultrasonic resonance imaging (ACURI) is an NDE technique that exploits the resonant behavior of a structure to extract information. This work applies the ACURI detection technique to multi-layered, multi-material composite plate samples with engineered disbonds and inclusions. Through-transmission C-scans of an undamaged sample are compared to samples with known defects. This investigation is carried out at 120 and 225 kHz to study the effect of resonance frequency excitation range on damage detection. It is shown that the majority of defects are easily detected. In some cases a difference in through thickness location is also discerned.