Influence of geometric parameters of surface electrode on electromechanical response of PDMS under impact loading

Abstract

In order to clarify the electromechanical coupling characteristics of polymer materials and extend their applications in MEMS (Micro-electromechanical Systems), electromechanical responses of PDMS (Polydimethylsiloxane) with different electrodes and thicknesses under different loading conditions have been performed experimentally and numerically. Basic electrical parameters measurement and quasi-static tensile experiment of PDMS specimens were conducted. Furthermore, the dynamic mechanical properties and polarization voltage of PDMS with different electrodes and thicknesses under different loading conditions have been studied by Split Hopkinson Pressure Bar (SHPB) system integrating with electrical output measuring system. Beyond that, Abaqus/Explicit numerical simulation of PDMS specimen under different loading conditions was carried out based on Yeoh viscoelastic model and Prony series, then the strain gradient and the flexoelectric coefficients were obtained. The results show that the maximum stress of PDMS increases with increasing of loading speed and decreases with increasing of thickness, the maximum polarization voltage increases with increasing of strain rate, the maximum polarization voltages of PDMS with “C” electrode and “+” electrode are about 14 times of that with circular electrode, the flexoelectric coefficients of PDMS are within the range of 10−11–10−9C/m.