| Under certain extreme working conditions,lack of lubrication or lubrication failure often causes lack of oil lubrication or even dry friction.As the core basic parts of my country’s major industrial and national defense equipment,ensuring the stable service of bearings under dry friction conditions is a key technology that needs to be overcome.Hot isostatic pressing silicon nitride（HIPSN）full ceramic bearings have excellent properties such as high and low temperature resistance,corrosion resistance,wear resistance,light weight,good accuracy retention,and long life.They are the key direction of future bearing development.However,the full ceramic bearing has been used for a long time under dry friction conditions,full ceramic bearings are severely worn,and their accuracy and life are greatly shortened.Therefore,it is necessary to consider introducing solid lubricating materials.PTFE has excellent properties such as low temperature resistance,self-lubrication,and easy processing.It is an excellent material to provide solid lubrication for full ceramic bearings.This paper takes the PTFE cage full ceramic bearing as the research object,takes the solution of bearing lubrication under dry friction conditions as the starting point to study the friction reduction and lubrication effect of the PTFE cage on the full ceramic bearing under dry friction.The specific content is as follows:（1）6009 full ceramic bearing model was established,and import the model into ADAMS for dynamic simulation analysis.The theoretical calculation and simulation results are compared to verify the correctness of the full ceramic bearing model.Considering the actual working situation,different speeds and radial loads are given to the bearing,and the force between the full ceramic bearing ball and the cage is calculated.（2）The friction and wear experiment of Si3N4 and PTFE was carried out using a friction and wear tester,and the friction coefficient and wear rate between the friction pairs were measured.The surface morphology of the grinding surface was observed by scanning electron microscope（SEM）.Summarize the influence of load,speed and other working conditions on the friction coefficient and wear rate,and analyze the PTFE anti-friction lubrication mechanism.（3）The Si3N4 powder lubrication experiment was carried out.The lubrication was carried out by introducing PTFE powder between the Si3N4 friction pairs to simulate the lubrication effect of the fine powder generated by the cage during the friction process on the bearing.Through comparative experiments with dry friction and water lubrication,the intervention and anti-friction effects of PTFE powder lubrication were demonstrated,and the influence of the quality of the surface transfer film on the friction coefficient under different loads was discussed.（4）The bearing life enhancement test machine carried out a comparison test of PTFE cage and plastic cage full ceramic bearing,by comparing the temperature rise and root mean square value change in the service process,verifying the friction reduction of the full ceramic bearing by the PTFE cage under dry friction conditions lubrication performance.Through a series of friction and wear experiments,combined with the comparison of the service performance of the PTFE cage under dry friction conditions,it is clarified that the PTFE has an anti-friction and lubrication effect on the internal components of the full ceramic bearing.The PTFE cage can be used for dry friction work.The full ceramic bearing provides lubrication under the condition. |
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