Study of the electrophysical characteristics of plastic lubricants

   Actively developing electric automobile transport assumes the creation of conductive lubricants. We pres­ent a setup designed to study the electrophysical properties of industrially produced and model plastic lubricants, as well as the samples of a similar consistency. The setup operates within the current frequency range from 0.1 to 1 kHz and includes a temperature-controlled measuring cell that allows changes in the sample thickness and temperature in the range from 20 to 120 °C. A method for determination of cur­rent-voltage characteristics with subsequent calculation of the specific electrical conductivity is proposed. The specific electrical conductivity of model plastic lubricants based on medical vaseline added with car­bon nanostructures (few-layer graphite fragments and their modified analogs) was studied using the de­veloped setup. Vaseline was used as a base model lubricant, since its rheological properties are similar to that of plastic lubricants and it does not contain any additional additives that can affect the measurement result. The electrically conductive properties of the dispersions of carbon nanostructures and their modi­fied analogs in vaseline were analyzed. It is shown that the introduction of carbon nanostructures into dielectric vaseline turns it into an electrically conductive material. The developed setup makes it possible to study the specific electrical conductivity of systems simulating plastic lubricants with a sufficient accuracy. The results obtained can be used to improve the methodology for studying the specific electrical conductivity of model and industrially produced plastic lubricants, including those with conductive additives.

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