This work presents the effects of five inorganic nanoparticles as additives, i.e., CNp (carbon nanotori particles), TiO2, MoS2, MoO3, and HcNT (halloysite clay nanotubes), in three different lubricants (oil-based, grease, and water-based). Nanolubricants were prepared by adding 1 wt% particles into each type of lubricant. Tribological properties of nanolubricants were determined and compared under anti-wear (AW) and extreme pressure (EP) conditions. CNp showed a decrease in coefficient of friction (COF) by 22% when added to water-based lubricant. Additionally, CNp demonstrated an improvement in limiting pressure of seizure (poz) of 74%, 52%, and 1621% for oil-based lubricant, grease, and water-based lubricant, respectively. Comparing 1 wt% CNp added to water-based lubricant with oil-based lubricant and grease, the improvements become outstanding under EP conditions. An increase in poz by 2479% compared to oil-based lubricant, and 789% compared to grease, was observed. In addition, a decrease of 66–69% in average wear scar diameter (AWSD) was obtained in comparison to oil-based lubricant and grease. Tribological mechanisms of carbon nanotori provide a rolling/sliding effect under AW conditions, and a load-bearing effect under EP conditions.
Bibliographical noteFunding Information:
This work was supported by FCFM-UANL , UDEM , and ITeE-PIB . Estefany Tovar Sifuentes gratefully acknowledges Conacyt-Mexico for the scholarship.
© 2021 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics