Self-lubricating film formation and ultra-low wear of PTFE/aluminum through anodization induced nano-microtextures

Polytetrafluoroethylene (PTFE) can transfer its material to counterfaces during sliding, forming a self-lubricating transfer film. Previous studies have demonstrated that surface morphology influences the formation of transfer films, and nano-microtextures have been shown to increase the wear of PTFE. In this study, nano-microtextures were created on the surface of aluminum alloys by phosphoric acid anodization. The results show that the nano-microtextures regulates the debris size, and the mechanical interlocking between the debris and the nano-microtextures facilitates the stabilization of the transfer film. The increase in surface energy boosts the capacity for debris adsorption on the surface, which promotes tribochemical reaction, enhancing the adhesion and cohesion of the transfer film and further improving the stability of the transfer film.