Preparation And Tribological Properties Of Tungsten Disulfide Composite Materials

As a transition metal sulfide,tungsten disulfide has potential development advantages in the field of tribology due to its special layered structure,excellent adsorption performance,and semiconductor properties.In this paper,the preparation and tribological properties of different tungsten disulfide composites were studied,the antifriction and antiwear properties of lubricating greases were tested,and their current carrying lubrication properties were investigated.The importance of additives was verified and analyzed using machine learning methods.The specific work and results are as follows:(1)Three kinds of IL/WS2 composite materials were prepared,and the tribological properties and electrical conductivity of the composite materials added to polyurea grease were studied.The results show that the optimal ratio of three kinds of ionic liquid modified composite materials in PUG for steel steel friction pairs is 2.0%;at the same time,compared to IW-2 and IW-4,the tribological properties of the composite material IW-8 modified with[OMIM]BF4 were significantly improved in polyurea resin.Under current carrying conditions,adding ionic liquid modified tungsten disulfide composite materials to copper copper friction pairs can improve friction reduction and wear resistance,while simultaneously reducing contact resistance.IW-2 with a chain length of 2 has the best electrical conductivity,but overall,IW-8 additive has the best comprehensive lubrication and electrical conductivity.(2)Fe3O4/WS2 and CuO/WS2 composites were prepared by one-step hydrothermal method,and the tribological properties and electrical conductivity of the composites added to polyurea grease were studied.The study found that in the steel/steel friction pair,the optimal proportions of Fe3O4/WS2 and CuO/WS2 in PUG are both 1.0%.Tribological experiments show that,compared with Fe3O4 and WS2,Fe3O4/WS2 and CuO/WS2 have significantly improved anti-wear properties.Under current-carrying conditions,when lubricating the copper-copper friction pair,1.0%CuO and 1.0%CuO/WS2 have lower contact resistance,and their antifriction and antiwear properties in polyurea grease have also been improved.(3)In order to quickly study the importance of grease additives,three regression prediction models based on the ensemble tree algorithm were established,and the feature contributions in different models were calculated.The results show that,in combination with the three ensemble tree models,in addition to the necessary Load and PUG features,the two features with the highest contribution to the friction coefficient are FW and CW,which is also in line with the experimental results;combined with the three ensemble tree models,it is found that only the Load feature has the largest impact on wear spot diameter at the same time,and it is much larger than other features,which is consistent with the impact of load on the experimental results in friction experiments.