Tribological Testing of PEEK for Aerospace Applications

Polyetheretherketone (PEEK) is a popular material for high performance bearing cages. It is now being considered for aerospace drive train applications due to the 80% weight savings compared to steel, but gaps remain in the understanding of PEEK's tribological performance. In this study, wear testing was performed to investigate the tribological performance of fiber reinforced PEEK under conditions that were representative of a typical aerospace drivetrain application. It was found that the processing conditions used can have a significant effect on the wear resistance. Further, it was found that both of the optimized PEEK materials tested experienced significantly less wear than the silver plated steel used as a baseline. Finally, it was determined that the friction loss of a PEEK bearing cage is expected to be higher than that of a silver plated steel one, but is still quite low with a coefficient of friction of approximately 0.02-0.03.