Role of hydrolysable nanoparticles on tribological performance of PPS-steel sliding pair lubricated with sea water

Tribological behaviors of polyphenylenesulphide (PPS) filled with hydrolysable nanoparticles, i.e. hexagonal boron nitride (BN), beta silicon nitride (Si3N4) or beta silicon carbide (SiC) nanoparticles, are investigated when sliding in sea water against a stainless steel. It is demonstrated that the addition of BN or SiC nanoparticles enhances significantly the tribological performance of PPS. In particular, SiC nanoparticles enhance the wear resistance of PPS by up to 100 times. Our work provides evidence that a robust tribofilm containing hydrolysis products of SiC, i.e. silica gel, protect the steel from wear and corrosion. Si3N4 nanoparticles play a positive role only if hydrolysis reaction occurs. This work paves the way for regulating interface structures and properties of polymer-metal pairs lubricated with sea water.