Modelling of Lamb waves for damage detection in metallic structures: Part I. Wavepropagation

Abstract

Lamb waves are the most widely used acousto-ultrasonic guided waves for damagedetection. The method is generally complicated by the coexistence of at least twohighly dispersive modes at any given frequency. Furthermore pure Lamb wavemodes may generate a variety of other modes by interacting with defects and/orby crossing different boundaries. Knowledge and understanding of Lamb wavepropagation is important for reliable damage detection. However, the theoreticalanalysis of guided wave scattering forms an extremely difficult problem. Thispaper reports an application of the local interaction simulation approach for wavepropagation in metallic structures. The focus of the analysis is on damage detectionapplications. The study also involves wave propagation in a piezoceramic actuator/sensordiffusion bond model in which one of the piezoceramics generates the thickness modevibration. The simulated results are validated experimentally. The results showthe potential of the method for wave propagation analysis in damage detectionapplications.