Ultrasonic Quasi-Rayleigh Waves - Propagation Properties and Detection of Mechanical Damage

Abstract

This article examines the propagation of quasi-Rayleigh waves and their trial application to detect defects in plate structures. With their specific propagation properties, quasi-Rayleigh waves have the potential to extend the scope of conventional ultrasound defect detection methods. This would enable detection across longer distances and with higher sensitivity, with earlier identification of surface defects in plate structures as a result. The article contains a basic description of quasi-Rayleigh waves, together with their propagation properties, with respect to a particular isotropic material (steel). The propagation of quasi-Rayleigh waves is then demonstrated using a smooth plate and a plate featuring a unilateral obstacle. The behaviours of propagating waves are determined using three approaches: analytical, numeric and experimental. The last part of the article provides a diagram and a description of the experimental measurement assembly and a case of detecting a surface defect in a plate structural part.