Enhancement of Underwater Tribological Properties of Hybrid PTFE/Nomex Fabric/Epoxy Resin Multilayer Composites by Mixed Graphite and MoS₂ Fillers

Abstract

This work studied the effect of mixed graphite and MoS₂ fillers on tribological properties of hybrid polytetrafluoroethylene (PTFE)/Nomex fabric/epoxy multilayer composites under water lubrication. A ring-on-block tribometer was used to perform the tribological test under dry sliding and water lubrication conditions. The worn surface was analyzed by scanning electron microscopy and optical microscopy. The results showed mixed fillers with 2.5 wt % graphite and 5 wt % MoS₂ had the best underwater tribological properties with the lowest friction coefficient (COF) of 0.067 and the lowest wear amount of 1.7 mg. Mixed fillers optimize epoxy resin properties, thereby increasing shore hardness, reducing water absorption, and improving wear resistance. This study also explained the reasons of the wear amount was higher in water than in dry sliding.