An Investigation on the Lateral Propagation of Ultrasound Waves in Multi-layered Structures

Abstract

Multi-layered structures have become a cornerstone in various sectors of industry. The use of composite materials continues to grow in aviation and automotive production. Solar photovoltaic modules, equally multi-layered structures, also become valuable elements in a carbon-free electricity generation system in the energy sector. Non-destructive testing using ultrasound C-scan techniques is frequently used for the inspection of these structures. However, lateral wave propagation through these structures may have more benefits. Thus, in this work, the authors investigate phenomena that occur when signals are emitted in a direction lateral to the plate's surface and make a comparison with recently obtained results for isotropic mono-layered structures, such as defect localization and edge detection. The plate under investigation is a multi-layered structure that consists of different materials bonded with an adhesive polymer. Experiments are designed to study the acoustic waves field resulting from parallel propagation of signals in layers with different stiffness properties. The investigation focuses on the propagating waves' interaction with discontinuities within the laminae, such as cracks or debonding. This work is an ongoing endeavour in which the first three authors, all PhD students, ordered in alphabetical order, contribute equally