Piezoelectric properties of paint sensor according to piezoelectric materials

The objective of this paper is to study the performance of piezoelectric materials on a piezoelectric paint sensor. The paper begins by presenting a fabrication method for a paint sensor with piezoelectric properties using piezoelectric materials. The paint sensor is composed of piezoelectric powder and epoxy resin in a 1:1 weight ratio. Five different piezoelectric materials, including three soft-type and two hard-type materials, were used and their piezoelectric properties compared in paint sensors and ceramic sensors. The paint sensors were cured using a steel mold for producing a uniform specimen size of 20 × 10 × 0.2 mm³, and an electrode was made on the upper and lower sides using silver paste. Poling treatment was then successfully performed at room temperature (20 ^◦C) under a 4 kV mm⁻¹ electric field for 30 min in order to activate the paint specimen as a sensor. Impact signals were monitored by measuring output voltage from the paint sensor in relation to impact force. The sensor's piezoelectric properties were then calculated using normalized piezoelectric properties. In addition, five different piezoelectric ceramic sensors were fabricated and their d₃₃ value measured to compare the sensitivity of paint sensors. As a result, Pb(Ni_1/3Nb_2/3)O₃-Pb(Zr, Ti)O₃ (PNN-PZT) powder showed higher sensitivity and higher piezoelectric properties than other piezoelectric materials in both paint and ceramic sensors.