Tribological Properties of Silicon Carbide‐Reinforced Polytetrafluoroethylene/Epoxy Resin Composite Coatings: Molecular Dynamics Simulation and Experimental Validation

Abstract

Wear‐induced failure of railway switch slide chairs remains a critical challenge, and conventional coating optimization still relies heavily on time‐consuming trial‐and‐error experiments. Therefore, molecular dynamics (MD) simulations combined with experimental investigations were employed to systematically investigate the effects of silicon carbide (SiC) content (0, 1, 3, 5, and 7 wt%) on the tribological properties of polytetrafluoroethylene/epoxy resin (PTFE/EP) composite coatings. Molecular models were constructed using Materials Studio, and friction behavior under room‐temperature dry sliding was simulated via shear displacement to obtain the coefficient of friction and wear rate, which were validated experimentally. Results show that increasing SiC content leads to a gradual increase in the coefficient of friction, while the wear rate exhibits a non‐monotonic trend, decreasing first and then increasing, with the optimum performance achieved at 5 wt% SiC (T5). The simulation and experimental results are in good agreement. Both indicate that T5 exhibits the lowest wear rate, corresponding to an MD‐derived wear parameter of 15.5% and an experimental wear rate of 0.21 × 10 −4  mm 3  N −1  m −1 . Wear morphology analysis reveals a transition from adhesive wear in the neat PTFE/EP coating to predominantly abrasive wear after SiC incorporation. These results confirm the reliability of the MD approach for designing PTFE/EP composite coatings.