Vibration and impact monitoring of a composite-wing model using piezoelectric paint

Abstract

This study investigates a piezoelectric paint sensor for large area sensing applications, and its sensing characteristics under dynamic loading conditions such as impact and vibration. The piezoelectric paint is composed of the Pb(Nb,Ni)O₃-Pb(Zr,Ti)O₃ (PNN–PZT) powder and epoxy resin. The PNN–PZT is a kind of soft piezoelectric material that offers many advantages such as high piezoelectric properties, easy poling, and so on. The PNN–PZT/epoxy paint sensor can be easily applied to various engineering structures, even to those having a complex geometry or curved shapes because of its flexibility. In this study, the PNN–PZT/epoxy paint was coated on a composite-wing model. One electrode was made on the upper surface of the piezoelectric paint, while the graphite/epoxy composite structure itself was used as the other electrode. Then poling was conducted at room temperature (20 °C) under a 4 kV/mm electric field for 10 min. When the composite-wing model was subjected to free-vibration, its vibration response was monitored by measuring the output voltage of the piezoelectric paint sensor; when the composite-wing model was impacted by an impact hammer, its impact signal was also measured by the piezoelectric paint sensor. The vibration and impact test results showed that the PNN–PZT/epoxy paint sensor captured the dynamic responses of the composite-wing structure very well. We believe that the piezoelectric paint sensor can be useful in many engineering applications such as real-time vibration and impact monitoring, damage detection, nondestructive structural health monitoring, and so on.

Keywords:

• piezoelectric
• composite
• 0–3 connectivity
• paint
• impact
• vibration
• monitoring
• sensor
• structural health monitoring

Acknowledgment

The author wishes to thank Prof. Jae-Hung Han in KAIST for providing measurement systems. This research was supported by Leading Foreign Research Institute Recruitment Program through the National Research Foundation of Korea funded by the Ministry of Science, ICT and Future Planning (2011-0030065), and supported by research funds of Chonbuk National University in 2012.