Determination of the Orthotropic Viscoelastic Tensor of Composites by means of the Pulsed Ultrasonic Polar Scan

Currently, advanced new materials such as fibre reinforced plastics (FRP) are being developed for the inclusion in load bearing components of modern industries. In order to select the most suited material for each specific component, accurate knowledge of its mechanical parameters is required. However, the complex nature of these FRPs, primarily expressed by a high degree of anisotropy, makes it difficult to determine their detailed mechanical behaviour. As a means to resolve this difficulty, the Pulsed Ultrasonic Polar Scan (P-UPS) has been developed. In this study, we propose and extend a recently developed two-stage characterization procedure based on amplitude and time-of-flight UPS recordings. This procedure has been tested on both virtual experiments, to show its effectiveness and robustness, as well as on real experimental measurements performed on unidirectional carbon-epoxy composites.