Photolithographically Home-Made PVDF Sensor for Cavitation Impact Load Measurement

Abstract

Piezoelectric PVDF sensors offer a unique option for the measurement of cavitation aggressiveness represented by the magnitude of impacts due to cavitation bubble collapses near walls. The aggressiveness measurement requires specific sensor shape and area, whereas commercial PVDF sensors are fabricated in limited geometry and size ranges. The photolithography method offers a possibility of production of home-made PVDF sensors of arbitrary shape and size. The methodology of a unique application of the standard photolithography method, which is commonly used for the production of printed circuit boards, is described in this paper. It enables mass production of high quality sensors contrary to laboratory techniques. This paper deals with the fabrication and the calibration of a photolithographically home-made PVDF sensor for the cavitation impact load measurement. The calibration of sensors was carried out by the ball drop method. Sensors of different sizes were fabricated by the photolithography method from a multi-purpose, both side metallized PVDF sheet. Commercial PVDF sensors of the same size were calibrated, and the calibration results were compared with the home-made sensors. The effect of size and the effect of one added protective layer of Kapton tape on a sensor sensitivity were investigated. The theoretical and numerical analysis was conducted to explain some issues during the ball impact.