Enhancing water-lubricated tribological performance of stainless steel with nano-MoS₂-PEG6000 modified epoxy resin coatings

In water-lubricated conditions, surface modification techniques that enhance the formation of water-lubricating films through surface treatment play a significant role. This paper proposes a method of applying a modified epoxy resin coating on stainless steel to improve its tribological performance under water lubrication. First, nano-MoS₂-PEG6000 fillers were prepared via a hydrothermal method. They were uniformly mixed into the epoxy resin and coated onto the surfaces of stainless steel and slipper pairs. Tribological experiments were conducted using a slipper-on-disk configuration, followed by characterization. Experimental results demonstrate that the nano-MoS₂-PEG6000 modified epoxy resin coating exhibits excellent water-lubrication properties, with the friction coefficient reduced by 66.4 % and the wear rate decreased by 99.2 %. The mechanism was revealed: MoS₂ reduces the shear force between rough peak contacts, while PEG6000 possesses strong hydration capacity, forming a stable water-lubricating film on the surface, thereby reducing friction. This study provides a novel approach for the tribological design of slipper pairs in water hydraulic pumps.