Abstract: The antifriction performance of the nano copper-based composite antifriction coating as applied on the P110S casing is tested with the HT-100 ball disc friction-wear testing machine.After being applied on the surface of the phosphorized coupling of the P110S casing, the coating is tested with the full-dimension screw-up and screw-off processes.The test result shows that the said coating produces an effective protective phosphorized layer upon the said casing, and remarkably reduces the friction factor of the specimen surface.The nano composite coating also has fine anti-galling performance.Compared with the coupling surface copperization process, the nano copper-based coating process has such advantages as excellent adhesion, high strength, good thermal conductivity, easy operation, high cost effectiveness and high-application value.