Study on the Influence of the MoS₂ Addition Method on the Tribological and Corrosion Properties of Greases

MoS2 lithium-based grease is suitable for lubrication protection between bearings at high temperatures and loads due to its excellent tribological properties. However, there is little research on the influence of different addition methods of MoS2 additive on its tribology and corrosion properties. In this work, eco-friendly vegetable oil was selected as the base oil, with MoS2 powder as the additive to synthesize lithium-based grease. The effects of different adding modes of MoS2 on the tribology and corrosion properties of the grease were studied. The experimental results showed that adding 0.01 wt% MoS2 before thickening (Method D) was more conducive to improving the tribological properties of lithium grease. The average friction coefficient was reduced by 26.1%, and the average wear scar diameter was reduced by 0.16 mm. After grinding and adding (Method B) 0.01 wt% MoS2, the corrosion inhibition efficiency of the steel sheet was as high as 96.97%. The reason was that the tribochemical reaction of MoS2 evenly distributed throughout the grease during friction, forming a thin friction film, reducing friction and wear. The protective film formed by MoS2 and GCr15-bearing steel improved the corrosion inhibition performance of the grease.