Termična analiza triboloških kontaktov s polimeri

This doctoral thesis investigates the thermal behaviour of polymer-containing tribological contacts, emphasizing the role of contact temperature in governing the friction and wear performance. Initially, a comprehensive experimental study was conducted on polymer/steel pin-on-disc sliding contacts under severe operating conditions, with a special focus on the effect of steel disc thickness—acting as a heat sink—on contact temperature, friction, and wear. The findings identified the key parameters influencing the contact temperature and demonstrated its critical role in determining the tribological performance of these systems, underscoring the importance of effective thermal management in such sliding contacts. Based on these findings, predictive, ready-to-use models were developed to estimate the maximum contact temperature in both (1) polymer/steel and (2) polymer/polymer pin-on-disc sliding configurations, covering a broad spectrum of material properties, contact geometries, and loading conditions. The developed models provide an important advancement in our understanding of the contact-temperature contributions in pin-on-disc experiments by employing several new modelling approaches. In particular, the models consider an energy balance for the whole tribological system of contacting bodies, and accounts for the dissipation of frictional heat by various dissipation modes: due to the convection, conduction and radiation. The ready-to-use model for polymer/steel contacts deliver highly accurate contact temperature predictions within the validated experimental range, with an uncertainty of approximately 3%. Similarly, the model developed for polymer/polymer sliding contacts demonstrated strong alignment between predicted and measured values under the specific contact conditions explored in this study, with a relative uncertainty of about 5%. This research not only enhances the understanding of thermal and tribological interactions in polymer-based sliding contacts but also provides practical modelling tools to aid in the design, optimization, and thermal management of polymer-containing tribological systems.