Distributed fiber-optic ultrasonic NDT via an MXene–PDMS photoacoustic emitter array

We integrate an optical fiber into a Ti3C2Tx MXene–PDMS anticorrosion coating to realize a photoacoustic emitter array (PEA) for distributed ultrasonic structural health monitoring. An L-shaped offset-splicing scheme creates four light-leaking nodes along one fiber, enabling near-simultaneous multi-point Lamb-wave excitation over a 30×30cm2 area on an Al- 1060 plate; echoes are captured by a fiber Bragg grating (FBG) receiver. he integrated system enables high-resolution imaging and precise localization of a 0.5×10mm surface defect with 97.4% accuracy, while the MXene’s layered “maze” architecture, strong Ti-C bonds, and surface terminations underpin corrosion resistance and long-term stability. Overall, the coating–fiber hybrid provides a compact, permanently embeddable platform for online, multi-point ultrasonic actuation and distributed sensing.