Nanoscale sliding friction behavior on Cu/Ag bilayers influenced by water film

Abstract Nanoscale sliding friction behavior of nanoparticle o n Cu/Ag bilayers influenced by water film is investigated by molecular dynamics (MD) simulation. The results show that the existence of water film aggravates the subsurface damage and the change of Cu/Ag interface microstructure, but improves the quality of groove surface and decreases the friction coefficient. Under the water-assisted sliding, there is a water-film thickness to minimize subsurface damage and friction coefficient, while make best groove surface quality. The results give an insight into the sliding friction mechanism of nanoparticle on Cu/Ag bilayers during dry and water-assisted sliding. Importantly, a meaningful guidance is provided for the amount of water used when the bilayer materials are subjected to nanoparticle sliding, thereby reducing the subsurface damage, inhibiting the change of interface microstructure, and improving the groove surface quality. The study is beneficial to develop the working performance and engineering application of bilayer materials.