Tribological applications of polytetrafluoroethylene (PTFE) are often limited by technological complexity to overcome its poor wear resistance. Here, a PTFE/polyetheretherketone (PEEK) heterolayer (HL) was proposed and evaluated as a new solid lubrication solution. Pin-on-disk tribometry found the lowest friction coefficient (μ) of 0.031 and ultralow wear for the PEEK/HL under typical conditions. The friction coefficient of the HL surpasses those of the state-of-the-art polymeric coatings/composites by at least 200%, and approaches that of highly lubricated interfaces. Mechanistic investigations revealed multi-length physical and chemical heterogeneity of the HL that best facilitates a tribofilm with high subsurface stability and surface instability. The technological simplicity and robustness of the HL’s high lubricity make it a promising new type of solid lubrication toward greater reliability and longevity.
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The authors acknowledge the support from the National Natural Science Foundation of China (51875153 and 51875152) and the Fundamental Research Funds for the Central Universities (JZ2021HGPA0062). We also gratefully thank Yu NING and Gang QIAN from Hefei University of Technology for their help in the spectroscopy analysis and Dr. ZHU from East China University of Science and Technology for his support in simulation work.
The authors have no competing interests to declare that are relevant to the content of this article.
Wei SUN. He received his Ph.D. degree in mechanical engineering from Hefei University of Technology, China, in 2022. Dr. Wei SUN’s past and current research can be broadly characterized as material tribology. More specifically, his research focuses on minimizing wear and friction of solid lubricant materials with the application of polymeric materials and two-dimensional (2D) materials, with a primary focus on understanding and improving the wear of PTFE composites and blends.
Xiaojun LIU. She is a professor at Mechanical Engineering Department, Hefei University of Technology, China. She received her M.S. degree in 1988 and received her Ph.D. degree in 2007 from Hefei University of Technology, China. His research interests are in the area of polymer tribology and soft material tribology.
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Sun, W., Ye, J., Song, Q. et al. Ultralow friction PTFE/PEEK heterolayer: A new solid lubrication approach toward simplicity. Friction 12, 120–135 (2024). https://doi.org/10.1007/s40544-023-0747-9