In order to investigate the lubrication and wear-reducing performance of polytetrafluoroethylene (PTFE) particle flow lubrication,the friction and wear tests of Si3N4 friction pairs under dry friction and PTFE powder lubrication were carried out under different loads.The influence of PTFE powder lubrication the tribological characteristics of the samples under different loads was analyzed.The wear and lubrication mechanism of the samples under different lubrication conditions were analyzed by SEM and EDS.The results show that the friction coefficient under PTFE powder lubrication is obviously lower than that under dry friction condition,and PTFE powder keeps stable lubrication during the experimental time.In the sliding friction process,PTFE powder forms a layer of transfer film adhering to the surface of the sample due to the action of pressure,so that the friction coefficient is in a continuous low state,which plays a good lubrication and protection role for the sample.With the increase of the load,the covering area and continuity of the transfer film become better and then worse,leading to the friction coefficient under PTFE powder lubrication decreases first and then increases.Therefore,PTFE powder under particle flow lubrication has good lubrication and wear-reducing effect,and has a very wide application prospect.