Non-destructive testing (NDT) of bonded assemblies

The SealedwithoUTaKiss project addressed the pressing need in the aerospace industry for reliable, cost-efficient inspection solutions for composite materials, which make up over 50% of the primary structures of new aircraft models. Given the rapid growth in air transport fleets and the rising market for Maintenance, Repair, and Overhaul (MRO) operations, there was an evident need for better inspection solutions to detect weak bonds and hard-to-find structural defects in adhesively bonded hybrid assemblies.

This EU-funded project aimed to enhance the detection of such defects by integrating non-destructive testing (NDT) methods, inline process inspection techniques, and mechanical testing. The project combined laser shock and ultrasonic guided wave techniques, achieving a Technology Readiness Level (TRL) 6 demonstrator capable of accurately identifying structural defects, including kissing bonds.

SealedwithoUTaKiss implemented mechanical adherence testing and conducted comparative experimental analyses of various NDT techniques to identify different defects in hybrid bonded assemblies. The project's solution aimed to facilitate the widespread use of adhesively bonded assemblies in the aerospace industry by providing highly reliable inspection methods during the manufacturing process.

The project consortium brought together expertise from different fields: GMI provided knowledge in composites, hybrid materials, and aircraft component manufacturing; BUL contributed with laser shock, inline inspection, and defect detection algorithm development; and TWI offered expertise in NDT techniques, ultrasonic guided waves, mechanical testing, and adhesives in bonding.

Overall, SealedwithoUTaKiss promised to deliver significant benefits to the European aerospace industry. These included the production of lightweight aircraft, improved performance, better fuel efficiency, reduced costs, and more environmentally efficient flight operations. By enhancing the reliability and cost-efficiency of inspecting adhesively bonded assemblies, the project aimed to ensure safer and more economical air travel.