Damage Size Quantification Using Lamb Waves by Analytical Model Identification

Abstract

Corrosion is a major concern for the aeronautic industry and providing structures with the intrinsic ability to monitor autonomously their health state is a major actual academic and industrial challenge. In this paper, detection, localization, and quantification of a damage representative of a corrosion damage using Lamb waves emitted and received by piezoelectric elements for the purpose of structural health monitoring of aeronautics aluminum structures is addressed. Semi-spherical holes of differ- ent sizes representing a calibrated corrosion pit are manufactured on a 2024 aluminum plate with four piezoelectric sensors bonded on it. Lamb waves are then recorded with one element used as an actuator and the other ones being used as sensors. A dedicated recording system provided by Cedrat Technologies is used to acquire Lamb waves data. It is demonstrated on this representative example that by using actual algorithms from the SHM literature, it is possible to detect, localize, and quantify this damage representative of an actual corrosion damage. These preliminary results are very encouraging before monitoring actual corrosion and fatigue damages which constitutes the main objective of the COQTEL project.