Temporal Enhanced Ultrasound as a Novel NDT Technique for Characterization of Defects in Composites

Abstract

Nondestructive Testing (NDT) methods are commonly employed to monitor manufacturing and in-service defects of composites. These defects include porosity, foreign object debris, impact-induced delamination and heat-induced resin degradation. Conventional ultrasonic methods such as pulse-echo analysis based on loss of signal amplitude are widely used for NDT. However, application of conventional ultrasonic methods is challenging for cases where the loss of signal is negligible, e.g., micro-porosities, micro-cracks, heat-damage or under-cured parts. Temporal-enhanced ultrasound (TeUS) is a novel non-invasive imaging technique that captures information from a temporal sequence of backscattered US radio frequency data obtained from a fixed location. Recent studies have demonstrated numerous effective applications of this technology for in vivo and ex vivo characterization of biological materials. In this paper, we demonstrate the feasibility of using TeUS as a novel, inexpensive NDT approach for composites inspection, and present the results of experiments designed to investigate its classification capability for composite defects.