To investigate the effect of deposition temperature on the tribological properties of CrN coatings,find a green lubricant suitable for the coatings,the CrN coatings were prepared by magnetron sputtering technique at different deposition temperatures.Their microstructure,mechanical properties,as well as friction and wear properties were evaluated by using X-ray diffraction,scanning electron microscope,atomic force microscope,scratch tester,nano-indentation and tribotester respectively.The results show that the CrN coatings deposited at 250 ℃ have the densest crystalline structure and the best mechanical properties.Tribological experiments show that the CrN coatings deposited at 250 ℃ exhibit the optimum tribological properties under both dry friction and soybean oil lubrication conditions.XPS analysis shows that the soybean oil undergoes a tribochemical reaction due to the presence of friction and forms a chemisorbed film on the coating surface.This film effectively reduces the friction and wear of the coatings.CrN coatings deposited at 250 ℃ have the optimum mechanical and tribological properties,and soybean oil is an excellent lubricant for CrN coatings.