Analytical study of piezoelectric paint sensor for acoustic emission‐based fracture monitoring

ABSTRACT Analytical study of piezoelectric paint, which provides insight about its key material behaviour in ultrasonic sensing, is the focus of this paper. Piezoelectric paint is a composite piezoelectric material that comprises tiny piezoelectric particles randomly dispersed within a polymer matrix phase. Acoustic emission (AE) technique has been used for non‐destructive evaluation (NDE) such as fracture monitoring in metal, concrete and composite structures. The feasibility of using piezoelectric paint for AE sensing has been demonstrated. In the context of piezoelectric paint‐based AE sensor, models for the key material properties of piezoelectric paint are reviewed first. The effect of piezoelectric ceramic volume fraction on paint sensor response is examined. A coupled field finite element model was established to carry out the electro‐mechanical analysis of piezoelectric paint sensor subjected to AE excitation. The simulation model for piezoelectric paint sensor is calibrated with experimental data. While more extensive research needs to be done to characterize piezoelectric paint sensor for fracture monitoring, such an analytical study proves to be very useful to the optimization of piezoelectric paint formulation and sensor geometry for AE sensor.