Friction and Wear Behaviors of Several Polymers Sliding Against GCr15 and 316 Steel Under the Lubrication of Sea Water

Ocean tribology, a new research field of tribology, is currently being established and developed. The tribological behaviors of polyether ether ketone (PEEK), poly(phenyl p-hydroxybenzoate) (PHBA), polyimide (PI), and perfluoroethylene propylene copolymer (FEP) sliding against GCr15 and 316 steel rings under the lubrication of sea water were studied and compared with that under the lubrication of pure water. The results show that the friction and wear behaviors of a polymer under the lubrication of aqueous medium are not only related to the properties of polymer itself, but also to the corrosive effect and lubricating effect of the medium. When a polymer slid against GCr15 steel under sea water lubrication, the friction coefficient and wear rate of polymer were much larger than that under pure water lubrication because of indirect corrosive wear. However, when sliding against corrosion-resistant 316 steel, polymers PEEK, FEP, and PI exhibited lower coefficients of friction and wear rates under sea water lubrication, this was attributed to better lubricating effect of sea water as a result of the deposition of CaCO3 and Mg(OH)(2) on the counterface. On the contrary, the friction coefficient and wear rate of PHBA sliding against 316 steel under sea water lubrication were larger than that under pure water lubrication, which may be related to the properties of PHBA itself.