Self-sensing FS Weld-bonded joints for structural monitoring

In the aerospace industry there is a constant search for lighter, better performing and economically beneficial solutions. To that effect, an alternative to the more common joining techniques such as riveting or screwing, Friction Stir Welding (FSW) emerged. This technique allows the manufacture of high-quality joints with complex geometry, reducing the production costs. This technique can be further improved if combined with adhesive application, forming hybrid joints, which exhibit better mechanical performance. However, in FSW welds, it is hard to monitor or inspect the integrity of the joint during its work-life and that unreliability factor is one of the main reasons why its application is not yet widely spread in the industry. Consequently, there is a need for a detailed analysis of the mechanical performance during the welding process and under a variety of loads. To achieve that goal, in this paper the application of Bragg sensors that allow the monitoring of deformations in both manufacturing and service moments is studied and results benchmarked against finite element models. This work aims to demonstrate the potential of a large-scale application of this technique in the aeronautical structures. (C) 2020 The Authors. Published by Elsevier B.V.