Bio-inspired ceramic scaffold reinforced PTFE composites achieving near-zero wear and self-lubrication under extreme conditions

Abstract

The development of high-performance polytetrafluoroethylene (PTFE) composites with excellent wear resistance and self-lubrication under heavy-load and high-speed conditions is urgently required for advanced tribological applications in many fields including aviation and aerospace, but remains a challenge. Human enamel, a natural composite capable of enduring millions of chewing cycles under pressures up to ~2.5 GPa, serves as an ideal model for advanced wear-resistant composites. Herein, a biomimetic design strategy is proposed to create PTFE composites with a cellular-structured ceramic scaffold reinforcement microstructure, inspired by the anti-wear effect of enamel rod/inter-rod structure. By utilizing the preferential load support effect and debris size control mechanism of ceramic scaffold, the bio-inspired composites achieve excellent wear resistance with effective self-lubrication. Furthermore, a polydopamine modification technology for PTFE component is employed to enhance the adhesion and stability of PTFE transfer films, thereby improving the self-lubrication performance of the composites. Consequently, the resulting composites exhibit outstanding tribological properties, especially characterized by near-zero wear and good self-lubricity under heavy loads and high speeds. This work will advance the development of high-performance self-lubricating composites suitable for extreme conditions. Furthermore, the proposed design strategy is expected to be applicable to other biological prototypes, enabling the creation of diverse high-performance functional composites.