Characterization of piezoelectric paint and its refinement for structural health monitoring applications

Piezoelectric paint is a composite piezoelectric material, due to its outstanding properties consisting of flexibility and conformability, it has been a great interest in structural health monitoring applications recently. The normal piezoelectric ceramics offer high piezoelectric properties, but are difficult to adhere on curly structural surfaces. For normal polymers, it offers high flexibility but missing the ability to transform the mechanical energy into the electrical energy, and vice versa. The piezoelectric paint combines the features of both, so it could be distributed on both even and uneven structural surface, as a sensor or actuator. This work starts with the development of the piezoelectric paint, followed by a systematic characterization of its mechanical and piezoelectric properties, which includes microstructure, Young's modulus, sensitivity and piezoelectric charge constant da1. The characterization results helps to understand the performance of the piezoelectric paint more deeply. Finally, a refinement method is demonstrated to improve the piezoelectricity of the paint. The results showed that the piezoelectricity was greatly improved and therefore its applications in structural health monitoring is widely expanded.