Lubrication performance of MoS2 and SiO2 nanoparticles as lubricant additives in magnesium alloy-steel contacts

• MoS2 and SiO2 nanoparticles are used as lubricant additives for magnesium alloy/steel contact.
• The optimum concentration of nano-SiO2 or nano-MoS2 in base lubricant is obtained.
• The MoS2 is more pronounced in terms of load carrying capacity and lubrication film stability.
• The wear mechanisms are explained in light of the experimental results.

The effects of the base lubricant with and without nanoparticles on the tribological behavior of magnesium alloy/steel contacts were investigated using a reciprocating sliding ball-on-flat tribometer. Three sets of contact conditions were used to evaluate the effect of concentration, the capacity of carrying load and the stability of the lubrication film, respectively. The results showed that the tribological properties of the base lubricant have been improved by adding the nanoparticles. As compared with the SiO2 nanolubricants, the positive effect of the MoS2 nanolubricants is more pronounced in terms of the load carrying capacity and the lubrication film stability. Mechanisms by which the nanolubricants improve tribological behaviors are discussed.