Revealing the Tribochemical Evolution of PTFE Transfer Films During Ambient Aging

Abstract

Previous studies have established the critical role of tribochemistry in the formation of protective transfer films in dry friction applications of polytetrafluoroethylene (PTFE) composites. However, the specific mechanisms driving these reactions remain incompletely understood. This research combines ambient aging with periodic tribochemical analysis to clarify the chemical evolution occurring in PTFE transfer films. Infrared spectroscopy revealed gradual oxidation in the films, and further interrupted thrust washer experiments on the oxidized tribofilms confirmed that oxidation does not significantly reduce wear in PTFE. These findings reinforce the idea of a positive feedback loop between tribochemical activity and filler reinforcement in PTFE composites.