Comparative Evaluation of GFRP Composites Using Air-Coupled Ultrasonic and Microwave NDT

Composite materials, such as Glass Fibre Reinforced Polymers (GFRP), are quickly gaining traction as a favoured material for many industries due to their wide applications. In this paper, a comparative study based on two methods—namely, Air-Coupled Ultrasonic Testing (ACUT) and Microwave Non-Destructive Testing (MW-NDT), for defect evaluation in GFRP composites is carried out. Both being contactless technologies, which means they do not require any couplant, and makes it best suited for materials like GFRP, especially for inspection during the manufacturing stage itself. ACUT and MW-NDT are found to be techniques complementary to each other and hence by combining the two methods, we could develop a sophisticated NDT approach.