FRICTION AND WEAR BEHAVIORS OF HYBRID PI/PTFE NANOCOMPOSITES ENHANCED WITH NANOPARTICLES

The friction and wear tests were executed for several Polyimide (PI)/Polytetrafluoroethylene (PTFE) composites enhanced with different nanoparticles, such as lipophilic nano-SiO2, nano-Cu, nano TiO2 and nano-Al2O3 utilizing a MMU-5G friction and wear tester. The experimental results indicate that the addition of nano-fillers significantly elevates the tribological properties of composites. When composed of 20% PTFE +15% nano-Cu, the PI-based ternary composite shows the highest wear resistance to further understand the wear mechanism of composites, a scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) were employed to examine the wear surfaces of composites and transfer films generated on worn surfaces. Distribution maps of characteristic elements by EDS imply that the variety of nano-fillers uncommonly affected the tribological behaviors of PI-based ternary composites. Moreover, SEM analysis demonstrates that the continuity of transfer film presents a positive relationship with the wear resistance of PI-based composites.