MoS2/PFPE固液复合润滑体系摩擦磨损性能研究OA

In order to acquire a solid-liquid composite lubrication method that exhibits outstanding friction and wear properties,a comprehensive investigation is carried out on the MoS2/PFPE solid-liquid composite lubrication system.Furthermore,a detailed analysis is conducted on its wear and lubricating mechanism,including the actual wear type and lubricating media composition.The friction coefficient of the MoS2/PFPE solid-liquid composite lubrication system is determined through a ball-disk friction test.The friction coefficient test result is compared with three common lubrication systems,which are MoS2 solid lubrication,PFPE oil lubrication,and PFPE oil lubrication modified with MoS2 powder.The test results of the ball-disk friction test show that compared with MoS2 solid lubrication,the friction coefficient of MoS2/PFPE solid-liquid composite lubrication,PFPE oil lubrication,and PFPE oil lubrication modified with MoS2 powder all exhibit an increase.However,the service lives of these three lubrication systems are significantly extended.And the initial friction coefficient of MoS2/PFPE solid-liquid composite lubrication is the lowest among these three lubrication systems.In order to analyze the wear performance after the friction coefficient test,the wear scar surface of the steel ball is studied through a surface profiler.The wear condition of the steel ball indicates that the wear resistance of the MoS2/PFPE solid-liquid composite lubrication system is better than that of the other two kinds of oil lubrication.Friction and wear properties of the MoS2/PFPE solid-liquid composite lubrication system show that it has the best comprehensive tribological performance among all lubrication systems tested.To investigate the wear and lubricating mechanisms of the MoS2/PFPEsolid-liquid composite lubrication system,various microscopic characterizations are carried out,including SEM,EDS and Laman spectrum.SEM images for the wear scar surface of test rings indicate the wear mechanisms of different lubrication systems.The wear type of MoS2 solid lubrication is abrasive wear.PFPE oil lubrication and PFPE oil lubrication modified with MoS2 powder show adhesive wear.The wear mechanism of the MoS2/PFPE solid-liquid composite lubrication system is the composite mechanism of abrasive wear and adhesive wear.EDS elemental analysis indicates the existence of Mo and S,which means there is a MoS2 transfer film at the friction interface of the MoS2/PFPE solid-liquid composite lubrication system.Laman spectrum shows the characteristic absorption of MoS2,which also verifies the existence of the MoS2 transfer film at the friction interface of the MoS2/PFPE solid-liquid composite lubrication system.Microscopic characterization results indicate that the lubricating mechanism of the MoS2/PFPE solid-liquid composite lubrication system is a synergistic lubrication effect of the MoS2 transfer film and PFPE oil.The existence of the MoS2 transfer film is the key reason why the MoS2/PFPE solid-liquid composite lubrication system shows better wear resistance and initial friction coefficient than those of PFPE oil lubrication and PFPE oil lubrication modified with MoS2 powder.To sum up,the MoS2/PFPE solid-liquid composite lubrication system can significantly extend the service life of the friction pair,while having relatively low initial friction coefficient and high wear resistance.This excellent comprehensive tribological performance profits from the co-existence of the MoS2 transfer film and PFPE oil.This article can provide theoretical support and data reference for the design of high-performance and long-life solid-liquid composite lubrication systems.