▎ 摘　　要

This study evaluates and compares the tribological behavior of multilayer 2D graphene (2D LG) and 3D graphene foam (3D GF), deposited by means of drop-casting process onto DLC/H-DLC film. Four series of lubrication systems (GCr15/DLC, GCr15/H-DLC, Al2O3/DLC and Al2O3/H-DLC) are designed and a targeted scheme of selecting different multilayer graphene material as DLC/H-DLC modifier is proposed to be suitable for different working conditions. The results emphasize the remarkable lubrication effect of 2D LG and 3D GF in controlling the humidity sensitivities of the tribological behavior of DLC/H-DLC film. The tribo-testing environment is controlled at a load of 5 N in moist air (32 +/- 2%) using bare GCr15 ball as counterbody. A low WR (7.22 x 10(-8) mm 3 N-1 m(-1), reduced by 40.91%) is achieved for DLC+3D GF film and a low COF (0.05, reduced by 82.69%) is achieved for H-DLC+2D LG film. Based on the experimental results, we find that the tribological properties of 2D LG and 3D GF are similar and suitable for low and high Hertz contact stress conditions, respectively. Different tribological behaviors are controlled by different tribological mechanisms. Raman investigations, XPS survey spectra, SEM-EDS and nanoindentation analyses of the material pairs indicate that the formation of complete and uniform transfer film with more ordered sp(2) hybrid structure induced by 2D LG/3D GF evolves the carbon tribofilm/ DLC(H-DLC) contact into self-organized graphene tribofilm/DLC(H-DLC) contact leading to such dramatic improvement in tribological properties. [GRAPHICS]