Study On The Properties Of MoS₂@C Filler Modified Polytetrafluoroethylene

Polytetrafluoroethylene(PTFE)plays an important role in many fields due to its excellent chemical stability,self-lubrication and other characteristics,but its service life is greatly reduced due to its easy wear in the process of use,which greatly restricts its development and application.In this paper,mechanical mixed layered Mo S2@C and flower spherical Mo S2@C prepared by hydrothermal method were selected as PTFE modification additives.The reaction conditions of preparing powder by hydrothermal method were investigated.The effects of different carbon content and microstructure of filler on friction properties were studied.The results of the study are as follows:1.In the process of hydrothermal powder preparation,the reaction temperature plays a decisive role in the reaction.If the reaction temperature is too low,although Mo S2@C powder can be generated,it cannot provide enough energy to maintain its stable microstructure;However,when the reaction temperature reaches a certain value,the reaction time only promotes the forward reaction,and has no effect on the microstructure of powder.2.Whether add layered or flower spherical Mo S2@C powder PTFE sample,its wear resistance has been greatly improved,which add layered powder sample optimal carbon content is 1%,its wear resistance is 82% higher than pure PTFE,different carbon content of the sample friction coefficient is V-shaped change,the wear rate is also V-shaped change;However,the optimum carbon content of the sample added with flower ball powder is 1.5%,and its wear resistance increases by 90%.For the sample added with flower ball powder,the friction system changes with the increase of carbon content,and the wear rate changes with the l-shape.3.In the process of friction at room temperature,pure PTFE mainly abrasive wear,and the addition of additives in the sample is mainly adhesive wear,friction process stripped by the abrasive chip will be under the action of force on the surface of the sample and the steel ball,the formation of anti-wear lubrication film.4.The addition of additives makes the sample also has good wear resistance at high temperature,which is the best performance of the sample with flower ball powder,one hour wear rate has been controlled at about 3%,while the wear rate of pure PTFE rose from 16% to 23% with the temperature increase;And from the point of view of its transfer on the surface of the grinding ball,pure PTFE has almost no transfer attached to the surface of the grinding ball,while the other two steel ball surface have a uniform and thick transfer film.5.Pure PTFE wear at high temperature in the form of adhesion wear,and the addition of modified powder sample of the wear form of adhesion wear and abrasive wear exist at the same time,adding modified powder sample it will be easier to form anti-wear lubrication film on the steel ball and its own friction area.