Micro-arc oxidation (MAO) technology can obviously improve the mechanical properties and surface properties of aluminum alloy.However,the ceramic layer obtained by MAO shows high roughness,which leads to great wear of aluminum alloy during friction.To improve the wear resistance of aluminum alloys,a composite film with excellent lubrication performance was prepared on the ceramic layer surface of aluminum alloy after MAO using hot pressed polyvinyl alcohol (PVA) and polyethylene glycol (PEG) polymers.The lubrication performance of the composite film was characterized under different frequencies,loads and lubrication conditions.X-ray diffraction (XRD) and Fourier transform infrared (FTIR) were used to analyze the formation mode and lubrication mechanism of the composite film.The results show that the composite film has good lubrication performance,and its friction coefficient is only 1/4 of that without the film.The composite film maintains good lubrication characteristics under dry friction,oil lubrication,and high-speed working conditions,but it will undergo local dissolution in water environment,resulting in poor lubrication performance.The network structure of the composite film and the self-lubricating characteristics of the polymer play an excellent lubricating role together.