Thermal Contact Resistance of Polymer Interfaces

by Gibbins, Josh

In this study an experimental program was carried out to determine the thermal contact resistance at polymer interfaces. Specifically, a polycarbonate to stainless steel interface along with a polycarbonate to polycarbonate interface were investigated. The thermal contact resistance at a stainless steel to stainless steel interface was also investigated for comparison purposes. Experimental data was obtained over a pressure range of approximately 600 - 7000 kPa, in a vacuum environment.

The experimental data was compared to the CMY plastic contact model, the Mikic elastic contact model and the SY elasto-plastic contact model to investigate the ability of such established thermal contact models to predict the thermal contact resistance at polymer interfaces. Based upon predictions made in regards to the mode of deformation of the asperities on the contacting surfaces the appropriate contact model showed good agreement with the experimental data for the stainless steel-stainless steel data set and the polycarbonate-stainless steel data sets. There was poor agreement between the all three contact models and the experimental data for the polycarbonate-polycarbonate data sets. It was determined that uncertainties in the proposed experimental method prevented an accurate measurement of the thermal contact resistance values for the polycarbonate-polycarbonate data sets.

The purpose of this investigation was to extend the use of established thermal contact models to polymer interfaces and to provide a comparison between the thermal contact resistance values of metal and polymer interfaces.

Thermal contact resistance for the polymer to metal interface was shown to be predicted by the Mikic elastic contact model in comparison to the metal to metal interface which was shown to be predicted by the CMY plastic contact model. The thermal contact resistance for a polymer interface was found to be on the same order as a metal interface.