Research On Friction And Wear Properties And Corrosion Resistance Of New Self-Lubricating Bearing Materials

Because the lubrication method of traditional bearing is not suitable for extremely harsh working environment,the research of solid self-lubricating bearing is very important.In this paper,aluminum bronze 9-4 and tin bronze 6-6-3 are used as matrix materials.Graphite and Mo S₂are of 1:1 proportion as Solid Self-Lubricating lubricants.Of all the lubricating materials,Inlaid Solid Self-Lubricating Bearing（ISSLB）are designed.45#steel and 2Cr13 stainless steel were used as friction pairs for friction and wear experiments.The corrosion resistance of copper alloy and friction pair was compared by electrochemical experiment and salt spray accelerated corrosion test,and the friction and wear resistance and corrosion resistance of copper base ISSLB materials were analyzed.In this thesis,the friction and wear properties（friction coefficient,wear amount,friction temperature）of aluminum bronze and tin bronze and ISSLB materials based on these two materials under different loads were studied through the friction and wear tests of aluminum bronze,aluminum bronze base ISSLB materials,tin bronze and tin bronze base ISSLB materials and 45#steel and 2Cr13 stainless steel under different loads.The friction and wear properties of the new self-lubricating bearing material and the traditional copper alloy under the same load were compared.The friction mechanism of various materials in the friction process was discussed.The influence and mechanism of C-Mo S₂composite solid lubricant on friction and wear properties were analyzed.According to the results of friction and wear experiments,the friction coefficient of copper base ISSLB material is lower than that of copper alloy,and the wear amount of copper base ISSLB material is much lower than that of copper alloy,and the wear amount of tin bronze base ISSLB material is lower than that of aluminum bronze base ISSLB material,and the surface wear is slighter.Due to the weak interlayer bonding force of graphite and Mo S₂,the solid lubricating film formed by both is easy to slip between layers.In general,because of the existence of solid lubrication film,copper base ISSLB material has better friction and wear properties.Through the three-electrode electrochemical test in 3.5 wt.%Na Cl solution,the corrosion resistance of the experimental materials was compared and analyzed,and the polarization curves,electrochemical impedance spectra（EIS）and Bode diagrams of each experimental material were obtained.Tafel fitting and equivalent circuit fitting were used to obtain information such as corrosion potential,corrosion current density and impedance value.The salt spray corrosion tank was injected with 3.5 wt.%Na Cl solution for 48 hours of continuous spray test.Electrochemical test results show that the impedance of aluminum bronze is significantly greater than that of tin bronze,which indicates that aluminum bronze has better corrosion resistance,and the corrosion resistance of 2Cr13 stainless steel is also better by EIS fitting comparison.From the comparison of corrosion morphology and quality,the salt spray accelerated corrosion test also shows that aluminum bronze and2Cr13 stainless steel have better corrosion resistance.The main reason is that aluminum is dissolved in copper matrix,forming a solid solution,which plays an effective strengthening role.The chromium element in 2Cr13 stainless steel will form a chromium oxide film to protect the substrate.