Abstract
Three kinds of new conductive lubricating greases were prepared using lithium ionic liquids as the base oil and the polytetrafluoroethylene (PTFE) as the thickener. These lithium ionic liquids ([Li(PEG)X]) were obtained by blending lithium salts (LiBF4, LiPF6 and LiNTf2) with poly(ethylene glycol) (PEG) because lithium salts have an extremely high solubility in PEG. The conductivities and contact resistances of the prepared lubricating greases were investigated using the DDSJ-308A conductivity meter and the reciprocating ball-on-disk UMT-2MT sliding tester. In addition, their tribological properties were investigated in detail. Scanning electron microscopy and X-ray photoelectron spectroscopy were employed to explore the friction mechanisms. The results suggest that the prepared lubricating greases have high conductivities and excellent tribological properties. The high conductivities are attributed to ion diffusion or migration of the lithium ionic liquids with an external electric field, and the excellent tribological properties depend on the formation of boundary protective films.
Article PDF
Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.Avoid common mistakes on your manuscript.
References
Lugt P M, Velickov S, Tripp J H. On the chaotic behavior of grease lubrication in rolling bearings. Tribol Trans52(5): 581–590 (2009)
Lugt P M. A review on grease lubrication in rolling bearings. Tribol Trans52(4): 470–480 (2009)
Winer W O. Molybdenum disulfide as a lubricant: A review of the fundamental knowledge. Wear10(6): 422–452 (1967)
Philip C H Mitchell. Oil-soluble MO-S compounds as lubricant additives. Wear100: 281–300 (1984)
Ye C F, Liu W M, Chen Y X, Yu L G. Room-temperature ionic liquids: A novel versatile lubricant. Chem Commun21: 2244–2245 (2001)
Hagiwara R, Ito Y. Room temperature ionic liquids of alkylimidazolium cations and fluoroanions. J Fluor Chem105: 221–227 (2000)
Holbrey J D, Seddon K R. The phase behavior of 1-alkyl-3-methylimidazolium tetrafluorobprates; ionic liquids and ionic crystals. J Chem Soci Dalton Trans13: 2133–2139 (1999)
Boon J A, Levisky J A, Pflug J L, Wilkes J S. Friedel-crafts reactions in ambient-temperature molten salts. J Org Chem51:480–483 (1986)
LaszloJ A, Compton D L. a-Chymotrypsin catalysis in imidazolium-based ionic liquids. Biotechnol Bioeng75: 181–186 (2001)
Bose S, Wijeratne A B, Thite A, Kraus G A, Armstrong D W, Petrich J W. Influence of chiral ionic liquids on stereo-selective fluorescence quenching by photoinduced electron transfer in a naproxen dyad. J Phys Chem B113: 10825–10829 (2009)
Welton T. Room-temperature ionic liquids: Solvents for synthesis and catalysis. Chem Rev99: 2071–2083 (1999)
Earle M J, Seddon K R. Ionic liquid: Green solvents for the future. Pure Appl Chem72: 1391–1398 (2000)
Zhao H. Innovative applications of ionic liquids as “green” engineering liquids. Chem Eng Commun193: 1660–1677 (2006)
Liu W M, Ye C F, Gong Q Y, Wang H Z, Wang P. Tribological performance of room-temperature ionic liquids as lubricant. Tribo Lett13: 81–85 (2002)
Cai M R, Liang Y M, Yao M H, Xia Y Q, Zhou F, Liu W M. Imidazolium ionic liquids as antiwear and antioxidant additive in poly(ethylene glycol) for steel/steel contacts. ACS Appl Mater Interfaces2: 870–876 (2010)
Jiménez A E, Bermúdez M D. Ionic liquids as lubricants for steel-aluminum contacts at low and elevated temperatures. Tribo Lett26: 53–60 (2006)
Yao M H, Liang Y M, Xia Y Q, Zhou F, Liu X Q. High-temperature tribological properties of 2-substituted imidazolium ionic liquids for Si3N4-steel contacts. Tribo Lett32: 73–79 (2008)
Cai M R, Liang Y M, Zhou F, Liu W M. Anticorrosion imidazolium ionic liquids as the additive in poly(ethylene glycol) for steel/Cu-Sn alloy contacts. Faraday Discuss156: 147–157 (2012)
Xia Y Q, Sasaki S, Murakami T, Nakano M, Shi L, Wang H Z. Ionic liquid lubrication of electrodeposited nickel-Si3N4 composite coatings. Wear262: 765–771 (2007)
Feng X, Xia Y Q. Tribological properties of Ti-doped DLC coatings under ionic liquids lubricated conditions. Appl Sur Sci258: 2433–2438 (2012)
Cai M R, Liang Y M, Zhou F, Liu W M. Tribological Properties of Novel Imidazolium Ionic Liquids Bearing Benzotriazole Group as the Antiwear/Anticorrosion Additive in Poly(ethylene glycol) and Polyurea Grease for Steel/Steel Contacts. ACS Appl Mater Interfaces3: 4580–4592 (2011)
Zheng W, Mohammed A, Hines Jr L G, Xiao D, Martinez O J, Bartsch R A, Simon S L, Russina O, Triolo A, Quitevis E L. Effect of Cation Symmetry on the Morphology and Physicochemical Properties of Imidazolium Ionic Liquids. J Phys Chem B115: 6572–6584 (2011)
Fan M J, Song Z H, Liang Y M, Zhou F, Liu W M. In sith formed ionic liquids in synthetic esters for signficantly improved lubrication. ACS Appl Mater Interfaces4: 6683–6689 (2012)
Lian Y F, Yu L G, Xue Q J. The antiwear and extreme pressure properties of some oil-water double soluble rare earth complexes. Wear196: 188–192 (1996)
Chen R J, Wu F, Li L, Xu B, Qiu X P, Chen S. Novel binary room-temperature complex system based on LiTFSI and 2-oxazolidinone and its characterization as electrolyte. J Phys Chem C111: 5184–5194 (2007)
Tamura T, Yoshida K, Hachida T, Tsuchiya M, Nakamura M, Kazue Y, Tachikawa N, Dokko K, Watanabe M. Physico-chemical properties of glyme-Li salt complexes as a new family of room-temperature ionic liquids. Chem Lett39: 753–755 (2010)
Hapiot P, Lagrost C. Electrochemical Reactivity in Room-Temperature Ionic Liquids. Chem Rev108: 2238–2264 (2008)
Cai M R, Zhao Z, Liang Y M, Zhou F, Liu W M. Alkyl Imidazolium Ionic Liquids as Friction Reduction and Anti-Wear Additive in Polyurea Grease for Steel/Steel Contacts. Tribol Lett40: 215–224 (2010)
Lu Q M, Wang H Z, Ye C F, Liu W M, Xue Q J. Room Temperature Ionic Liquid 1-Ethyl-3-Hexylimidazolium-Bis(trifluoromethylsulfonyl)-Imide as Lubricant for Steel-Steel Contact. Tribol Inter37: 547–552 (2004)
Fan X Q, Xia Y Q, Wang L P, Pu J B, Chen T D, Zhang H B. Study of the Conductivity and Tribological Performance of Ionic Liquid and Lithium Greases. Tribol Lett53: 281–291 (2014)
Mu Z G, Zhou F, Zhang S X, Liang Y M, Liu W M. Effect of the functional groups in ionic liquid molecules on the friction and wear behavior of aluminum alloy in lubricated aluminum-on-steel contact. Tribo Inter38: 725–731 (2005)
Kajdas C. Importance of anionic reactive intermediates for lubricant component reactions with friction surfaces. Lub Sci6: 203–228 (1994)
Wang H Z, Lu Q M, Ye C F, Liu W M, Cui Z J. Friction and wear behaviors of ionic liquid of alkylimidazolium hexafluorophosphates as lubricants for steel/steel contact. Wear256: 44–48 (2004)
Xia Y Q, Wang S J, Zhou F, Wang H Z, Lin Y M, Xu T. Tribological properties of plasma nitrided stainless steel against SAE52100 steel under ionic liquid lubrication condition. Tribo Inter39: 635–640 (2006)
Jimenez A E, Bermudez M D, Iglesias P, Carrion F J, Martnez-Nicolas G. 1-N-alkyl-3-methylimidazolium ionic liquids as neat lubricants and lubricant additives in steel-aluminium contacts. Wear260(7–8): 766–782 (2006)
Fan M J, Liang Y M, Zhou F, Liu W M. Dramatically improved friction reduction and wear resistance by in situ formed ILs. RSC Advances2: 6824–6830 (2012)
Song Z H, Fan M J, Liang Y M, Zhou F, Liu W M. Lithium-Based ILs: In Situ-Formed Lubricant Additive Only by Blending. Tribol Lett49: 127–33 (2013)
Author information
Authors and Affiliations
Corresponding author
Additional information
This article is published with open access at Springerlink.com
Xiaoqiang FAN. He is currently a Master-PhD student at Lanzhou Institute of Chemical Physics, Chinese Academy Science. He received his Bachelor degree in 2011 from Qingdao University of Science & Technology. His research interests are focused on preparation and tribological property investigation of conductive lubricating greases.
Yanqiu XIA. He got his PhD degree from Northeastern University in 1998. He joined Lanzhou Institute of Chemical Physics, Chinese Academy Science in 2008. His current research interests cover high performance lubricants and functional materials, lubrication principle and technology. He has published more than 90 journal papers and possesses 5 patents.
Liping WANG. He got his PhD degree from Lanzhou Institute of Chemical Physics in 2007. He is currently a group leader at Lanzhou Institute of Chemical Physics, Chinese Academy Science. His research interests cover solid film materials, lubricating materials and space tribology. He has published over 85 journal papers, authorized 10 patents and gained a number of national scientific awards.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.
To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/.
About this article
Cite this article
Fan, X., Xia, Y. & Wang, L. Tribological properties of conductive lubricating greases. Friction 2, 343–353 (2014). https://doi.org/10.1007/s40544-014-0062-2
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s40544-014-0062-2