A Flexible Thin-Film Magnetostrictive Patch Guided-Wave Transducer for Structural Health Monitoring

Structural health monitoring (SHM) technology has attracted more and more attention in aerospace and energy industries as it may detect and monitor early degradation and damage in the structures and thus avoid life and financial loss. Guided wave (GW) based inspection is very useful for the SHM of thin-walled structures due to its capability for long-distance and wide-range inspection with high sensitivity. However, the lack of small and high-performance transducers seriously limits the development of GW-based SHM technology. In this paper, a thin-film magnetostrictive patch transducer (MPT) that can generate and receive single-mode and almost nondispersive GW is proposed. The new transducer is composed of an alloy patch and a double-layer flexible printed circuit (FPC). Firstly, the basic structure and principle of the proposed transducer are presented and analyzed. Compared with current single-mode GW transducers, the main advantages of the proposed transducer are lightweight, flexibility, and high transduction efficiency. Both the numerical simulation and experimental results validate that the new transducer has good performance in generating and receiving single and almost nondispersive S0 mode GW in an aluminum plate. It is very promising to be applied for the SHM in curved thin-walled structures.