CrCN coating was deposited on 304 stainless steel by magnetron sputtering technique.The surface morphology,coating thickness,mechanical properties,phase composition and chemical valence states of the coatings were analyzed by field emission scanning electron microscopy,atomic force microscopy,nano-indentation instrument,Vickers hardness tester,X-ray diffraction and X-ray photoelectron spectroscopy,respectively.The tribological properties of CrCN coating under glycerol lubrication were evaluated with multifunctional friction and wear testing machine,and the results were compared with those under PAO6 lubrication.CrCN coating constructed on stainless steel surface by PVD has excellent mechanical properties.The surface of the coating is compact and smooth,and the roughness is only 1.01 nm,and the hardness of the coating is about 14.39 GPa.Compared the tribological properties of steel/steel system and steel/CrCN system lubricated with glycerol,it is found that the steel/CrCN system exhibits excellent tribological properties under glycerol lubrication.When the load is 0.5 N,the friction coefficient of steel/CrCN system lubricated with glycerol can be as low as 0.01,which is much lower than that lubricated with PAO6.XPS analysis of wear marks shows that during the friction process,glycerol experiences a tribochemical reaction and forms a FeOOH layer on the contact surface of the CrCN coating.The glycerol and some of its major degradation products are further adsorbed on the FeOOH layer to form a fluid lubrication layer,which effectively reduces friction and wear.