Study of microwave responses on layered woven CFRP composites

Abstract

Woven carbon fibre reinforced polymer (CFRP) have been widely used in the airline industry. The main challenge of microwave inspection on woven CFRPs is the complex electromagnetic responses related to their layered-woven structures and associated defect (e.g., impact damage). This work focuses on the simulation study of microwave responses for woven CFRPs based on microwave open-ended waveguide (OEW) system in K-band. Simulation studies of woven composites with different weaving structures are carried out through structural parameters including width, gap between fibres, ply thickness and number of plies. The simulation results suggest that gap and ply thickness significantly affect frequency shift in the response, whereas woven texture and number of plies are related to occurrences of multiple resonances/ripples. In the experiment, we examine microwave responses of a 12-layers, 5HS woven composite in areas of with and without impact damage. The initial experimental results show good agreement with the simulation. The understanding of microwave responses related to woven CFRP structures is the foundation for future development of defect characterisation technique and inverse problem solving on woven composites.