Influence of the Electrode Surface Roughness on the Electrical Conductivity of Pure Paraffin

A comprehensive theory of the conduction processes in dielectric liquids is needed to describe their behavior from low to high field strengths. To investigate the conductivity of dielectric liquids a paraffin with low self-conductivity and well-defined chemical structure is used. Particularly at higher field strengths the material and surface of the electrodes has to be considered as well. It is shown, that ground and polished electrodes of stainless steel reveal different behavior during current measurements. Furthermore, particularly at high field strengths long-time measurements are needed to reach steady state conditions. The current measurement employing polished electrodes shows great scattering. Due to the polishing process several surface irregularities became apparent. Hence, for current measurements the electrode material and surface treatment of the electrodes are of great importance.