Molybdenum disulfide (MoS2), as a high-quality solid lubricating material, has good antifriction, wear resistance and bearing capacity. Molybdenum disulfide (MoS2) film has a layered structure, and the particles that make up the deposited film have low hardness and high stability.
Using MoS2 to improve the surface bearing capacity of automobile gears has become a research hotspot, and scholars at home and abroad have done a lot of research. R. I. Amaro et al. [39] obtained MoS2 lubricating film on spline gear by magnetron sputtering, which effectively reduced friction and improved fatigue life limit at high speed. K. Holmberg and others adopt MoS2 / Ti composite coating technology, which can further reduce the friction coefficient. The friction coefficient can be as low as 0.07 at room temperature, which can effectively reduce the friction and wear of friction pairs during operation. R. C. Martins et al. Conducted FZG bench test on automobile gears coated with molybdenum disulfide composite coating. The temperature and friction coefficient of automobile gearbox of MoS2 coated automobile gears operating under the condition of 5-level load of 3000 R / min decreased significantly. Japan’s Nissan and Mazda Automobile companies have applied the surface molybdenum disulfide coating technology in the development and practice of transmission gears. The main principle is that after plating MoS2 film, 2 ~ 3 particles are produced on the tooth surface μ M soft coating can reduce the local maximum meshing contact stress and surface friction coefficient of the tooth surface, and improve the lubrication condition of automobile gears during meshing.
As shown in the figure, the fatigue life of automobile gears made of different materials and automobile gears coated with molybdenum disulfide (MoS2) surface are compared. In the figure, steel grade A (1cr-0.4mo) is common gear steel, steel grade B is vanadium added gear steel, and steel grade C is Mn and Mo incremental gear steel. The test results show that after molybdenum disulfide coating treatment, the smoothness of gear surface is significantly improved after initial meshing operation, and the fatigue life is increased by more than three times.