Discharge Poling and Poly(Vinylidene Fluoride) Films.

摘要

A new poling technique was developed which is significantly different from the two conventional poling techniques; direct poling and corona poling. The present technique is based on the fact that the application of higher poling fields to poly(vinylidene fluoride) PVF2 films produces higher piezoelectric and pyroelectric responses but with a significantly higher risk of sample breakdown. This risk can be reduced by employing an active current limiter in the poling circuit. Experiments show that the risk of breakdown was significantly decreased by employing a discharge element connected in series with the sample. The element consists of a metal spark gap and a high resistance (1 G omega) connected in series which works as a pulse shaper by suppressing the initial surge current and shutting down the current with a suitable time constant.