Hybrid of micro-aramid and nano-alumina prominently enhanced the wear resistance of polytetrafluoroethylene composites

Abstract

Polymer self-lubricating composites are key in reducing energy consumption from friction, boasting self-lubrication, remarkable wear, and corrosion resistance. This study delves into the unexpected synergy between micro-aramid and nano-Al₂O₃ in enhancing PTFE’s wear resistance. The results exhibit that the optimal hybrid of 15 vol.% micro-aramid and 1 vol.% nano-Al₂O₃ particles enhanced the PTFE composites has carried out the best tribological properties, showing synergistic anti-friction and anti-wear effects and obtaining the very low wear rate of 8.73 × 10⁻⁷ mm³/Nm, which is decreased by 53% and 98.7% in comparison with separate enhancement of the PTFE composites with 15 vol.% micro-aramid and 1 vol.% nano-Al₂O₃, respectively. In-depth characterization and analysis of the friction interface are confirmed that PTFE generating carboxylic acid groups during the friction process chelated with the dual steel surface, micro-aramid producing the interaction of the strong polarity with the dual steel, and mechanical stress and high flash temperature promoting friction sintering of nano-Al₂O₃ to enhance bearing capacity are cooperatively endowed a robustness protective tribofilm with easy shearing and high bearing properties, which effectively enhances the tribological properties of PTFE composites, providing a reference for the research and design of new nano composites with ultra-low wear and self-lubricating properties.