On dry sliding friction and wear behavior of PPESK filled with PTFE and graphite

Novel poly(phthalazinone ether sulfone ketone) (PPESK) resins have become of great interest in applications such as bearing and slider materials. In this paper, dry sliding wear of polytetrafluoroethylene (PTFE) and graphite-filled PPESK composites against polished steel counterparts were investigated on a block-on-ring apparatus at the same sliding velocities and different loads. The results indicated that the addition of 5–25 wt% PTFE and 5–30 wt% graphite contribute to an obvious improvement of tribological performance of PPESK at room temperature. Worn surfaces were investigated using a scanning electron microscope (SEM). As a result, the friction coefficient and wear rate of the PPESK composites decreased gradually with addition of fillers. A moderately low friction coefficient and specific wear rate were reached when the filler contents were above 20 wt%. The mechanical properties of PPESK composites were also investigated. The tensile and impact strength of PPESK composites decrease slightly as the addition of fillers contents were below 15 wt%.