Investigation on in-situ sprayed, annealed and corona poled PVDF-TrFE coatings for guided wave-based structural health monitoring: From crystallization to piezoelectricity

Large-area, lightweight and flexible sensing networks are highly demanded in complex (either structural topology or material property) health monitoring (SHM) applications. Development of piezopolymer offers a feasible solution. In pursuit maximum exploitation their functionality, the optimal fabrication technique requires to be investigated first. this study, PVDF-TrFE coatings were in-situ fabricated directly functionalized on surfaces consecutive processing steps as spray, thermal annealing, corona poling. The conditions, including annealing temperature/time poling voltage/duration, correlated with crystallinity, ferroelectric phase, morphology, polarization, final piezoelectricity, through systematic study. With help various characterization methods, conditions functional performance identified rationalized. To study feasibility thus-prepared transducing guided waves, host structures sensors made such interrogated by passive acoustic emission active ultrasonic transmission validate actuation capability, respectively. developed possess excellent novel configuration networks, lightweight, ultrathin, flexible, rapid-prototyping adhesive-free features, manifesting high adaptability, consistency, negligible inter-path interference, minimal extra penalty for robust SHM system.