Abstract
Effective lubrication has been achieved under vacuum conditions by employing MoS2 as a solid lubricant. The primary reason for its ability to reduce friction is attributed to its crystal structure, which allows easy shearing of MoS2 layers. This research explores the possibilities of utilizing MoS2 in soluble and insoluble forms to improve the performance of tribological systems. In this study, spherical rolling elements were coated with Ti–MoS2 and their tribological performance was evaluated in a ball-on-rod tribometer operating in boundary-lubricated (PAO ISO 10 oil) conditions. The results of these tests were compared with similar tests performed on uncoated steel specimens using PAO ISO 10 oil with and without a molybdenum dialkyldithiocarbamate (MoDTC) additive. The L50 fatigue lives of M50 rods tested against Ti–MoS2 coated balls were found to be similar to those obtained from tests performed on uncoated steel specimens using oil with MoDTC (1 wt%); that is, the L50 fatigue lives of M50 rods were improved by more than a factor of 2 in both cases. Tribofilms generated on M50 rods during testing with Ti–MoS2 coated balls in neat oil and uncoated balls in MoDTC (1 wt%) mixed oil were observed to be similar. Wear track analysis on M50 rods tested against Ti–MoS2 coated balls indicated that the tribofilms are mixtures of MoS2 and amorphous hydrocarbon (a-C:H). A possible mechanism for the formation of the a-C:H on the counterface is proposed based on the experimental investigations in this study. Further, it is concluded that the Ti–MoS2 coating on the spherical rolling elements functions as an MoS2 additive source to the lubricating oil rather than as a tribological coating.
Similar content being viewed by others
References
Winer, W.O.: Molybdenum disulfide as a lubricant: a review of the fundamental knowledge. Wear 10, 422–452 (1967)
Savan, A., Pflüger, E., Voumard, P., Schröer, A., Simmonds, M.: Modern solid lubrication: recent developments and applications of MoS2. Lubr. Sci. 12, 185–203 (2000)
Khare, H.S., Burris, D.L.: The effects of environmental water and oxygen on the temperature-dependent friction of sputtered molybdenum disulfide. Tribol. Lett. 52, 485–493 (2013)
Khare, H.S., Burris, D.L.: Surface and subsurface contributions of oxidation and moisture to room temperature friction of molybdenum disulfide. Tribol. Lett. 53, 329–336 (2013)
Mitchell, P.C.H.: Oil-soluble MO-S compounds as lubricant additives. Wear 100, 281–300 (1984)
Wan, G.T.Y., Spikes, H.A.: The behavior of suspended solid particles in rolling and sliding elastohydrodynamic contacts. Tribol. Trans. 31, 12–21 (1988)
Stupp, B.: Synergistic effects of metals co-sputtered with MoS 2. Thin Solid Films 84, 257–266 (1981)
Steinmann, M., Müller, A., Meerkamm, H.: A new type of tribological coating for machine elements based on carbon, molybdenum disulphide and titanium diboride. Tribol. Int. 37, 879–885 (2004)
Zabinski, J.S., Donley, M.S., Walck, S.D., Schneider, T.R., Mcdevitt, N.T.: The effects of dopants on the chemistry and tribology of sputter-deposited MoS2 films. Tribol. Trans. 38, 894–904 (1995)
Stoyanov, P., Chromik, R.R., Goldbaum, D., Lince, J.R., Zhang, X.: Microtribological performance of Au–MoS2 and Ti–MoS2 coatings with varying contact pressure. Tribol. Lett. 40, 199–211 (2010)
Scharf, T.W., Kotula, P.G., Prasad, S.V.: Friction and wear mechanisms in MoS2/Sb2O3/Au nanocomposite coatings. Acta Mater. 58, 4100–4109 (2010)
Singh, H., Mutyala, K.C., Mohseni, H., Scharf, T.W., Evans, R.D., Doll, G.L.: Tribological performance and coating characteristics of sputter deposited Ti doped MoS2 in rolling and sliding contact. Tribol. Trans. 58, 767–777 (2015)
Singh, H., Mutyala, K.C., Evans, R.D., Doll, G.L.: An investigation of material and tribological properties of Sb2O3/Au-doped MoS2 solid lubricant films under sliding and rolling contact in different environments. Surf. Coat. Technol. (2015). doi:10.1016/j.surfcoat.2015.05.049
Singh, H., Mutyala, K.C., Mohseni, H., Scharf, T.W., Evans, R.D., Doll, G.L.: Tribological behavior of Ti containing MoS2 in sliding and rolling contact. Tribol. Lubr. Technol. 2, 22–24 (2015)
Scharf, T.W., Prasad, S.V.: Solid lubricants: a review. J. Mater. Sci. 48, 511–531 (2013)
Muratore, C., Voevodin, A.A.: Chameleon coatings: adaptive surfaces to reduce friction and wear in extreme environments. Annu. Rev. Mater. Res. 39, 297–324 (2009)
Sliney, H.: Solid lubricant materials for high temperatures—a review. Tribol. Int. 15(5), 303–315 (1982)
Donnet, C., Erdemir, A.: Solid lubricant coatings: recent developments and future trends. Tribol. Lett. 17, 389–397 (2004)
Chhowalla, M., Amaratunga, G.: Thin films of fullerene-like MoS2 nanoparticles with ultra-low friction and wear. Nature 407, 164–167 (2000)
Rapoport, L., Leshchinky, V., Volovik, Y., Lvovsky, M., Nepomnyashchy, O., Feldman, Y., Popovitz-Biro, R., Tenne, R.: Modification of contact surfaces by fullerine-like solid lubricant nanoparticles. Surf. Coat. Technol. 163–164, 405–412 (2003)
Rabaso, P., Dassenoy, F., Ville, F., Diaby, M., Vacher, B., Le Mogne, T., Belin, M., Cavoret, J.: An investigation on the reduced ability of IF-MoS2 nanoparticles to reduce friction and wear in the presence of dispersants. Tribol. Lett. 55, 503–516 (2014)
Yamamoto, Y., Gondo, S.: Friction and wear characteristics of molybdenum dithiocarbamate and molybdenum dithiophosphate. Tribol. Trans. 32, 251–257 (1989)
Unnikrishnan, R., Jain, M., Harinarayan, A., Mehta, A.: Additive–additive interaction: an XPS study of the effect of ZDDP on the AW/EP characteristics of molybdenum based additives. Wear 252, 240–249 (2002)
Martin, J., Grossiord, C., Varlot, K.: Synergistic effects in binary systems of lubricant additives : a chemical hardness approach. Tribol. Lett. 8, 193–201 (2000)
Grossiord, C., Varlot, K., Martin, J., Le Mogne, T., Esnouf, C., Inoue, K.: MoS2 single sheet lubrication by molybdenum dithiocarbamate. Tribol. Int. 31, 737–743 (1998)
Miklozic, K.T., Graham, J., Spikes, H.A.: Chemical and physical analysis of reaction films formed by molybdenum dialkyl-dithiocarbamate friction modifier additive using Raman and atomic force microscopy. Tribol. Lett. 11, 71–81 (2001)
Yue, W., Fu, Z., Wang, S., Gao, X., Huang, H., Liu, J.: Tribological synergistic effects between plasma nitrided 52100 steel and molybdenum dithiocarbamates additive in boundary lubrication regime. Tribol. Int. 74, 72–78 (2014)
Graham, J., Spikes, H.A., Jensen, R.: The friction reducing properties of molybdenum dialkyldithiocarbamate additives: part II—durability of friction reducing capability. Tribol. Trans. 44, 637–647 (2001)
Graham, J., Spikes, H.A., Korcek, S.: The friction reducing properties of molybdenum dialkyldithiocarbamate additives: part I—factors influencing friction reduction. Tribol. Trans. 44, 626–636 (2001)
Jeng, Y., Hwang, S., Fong, Z., Shieh, J.: The effects of adding molybdenum dithiocarbamate additive to a sulfur-phosphorus gear oil on two roller apparatus performance. Lubr. Eng. 58(2), 9–15 (2002)
Bec, S., Tonck, A., Georges, J.M., Roper, G.W.: Synergistic effects of MoDTC and ZDTP on frictional behaviour of tribofilms at the nanometer scale. Tribol. Lett. 17, 797–809 (2004)
Neville, A., Morina, A., Haque, T., Voong, M.: Compatibility between tribological surfaces and lubricant additives-How friction and wear reduction can be controlled by surface/lube synergies. Tribol. Int. 40, 1680–1695 (2007)
Morina, A., Neville, A., Priest, M., Green, J.H.: ZDDP and MoDTC interactions in boundary lubrication-the effect of temperature and ZDDP/MoDTC ratio. Tribol. Int. 39, 1545–1557 (2006)
Morina, A., Neville, A.: Understanding the composition and low friction tribofilm formation/removal in boundary lubrication. Tribol. Int. 40, 1696–1704 (2007)
Morina, A., Neville, A.: Tribofilms: aspects of formation, stability and removal. J. Phys. D Appl. Phys. 40, 5476–5487 (2007)
Donnet, C., Erdemir, A.: Historical developments and new trends in tribological and solid lubricant coatings. Surf. Coat. Technol. 180–181, 76–84 (2004)
Mutyala, K.C., Singh, H., Evans, R.D., Doll, G.L.: Deposition, characterization, and performance of tribological coatings on spherical rolling elements. Surf. Coat. Technol. (2015). doi:10.1016/j.surfcoat.2015.06.075
Bunshah, R.F., Deshpandey, C.V.: Plasma assisted physical vapor deposition processes: a review. J. Vac. Sci. Technol. Vac. Surf. Film 3, 553–560 (1985)
Kelly, P.J., Arnell, R.D.: Magnetron sputtering: a review of recent developments and applications. Vacuum 56, 159–172 (2000)
Vidakis, N., Antoniadis, A., Bilalis, N.: The VDI 3198 indentation test evaluation of a reliable qualitative control for layered compounds. J. Mater. Process. Technol. 143–144, 481–485 (2003)
Lubrecht, A.A., Venner, C.H., Colin, F.: Film thickness calculation in elasto-hydrodynamic lubricated line and elliptical contacts: the Dowson, Higginson, Hamrock contribution. Proc. Inst. Mech. Eng. Part JJ. Eng. Tribol. 223, 511–515 (2009)
Evans, R.D., Cogdell, J.D., Richter, G.A., Doll, G.L.: Traction of lubricated rolling contacts between thin-film coatings and steel. Tribol. Trans. 52, 106–113 (2008)
Weibull, W.: A statistical distribution function of wide applicability. ASME J. Appl. Mech. 103, 293–297 (1951)
Abernethy, R.B.: An overview of Weibull analysis. The New Weibull Handbook: Reliability & Statistical Analysis for Predicting Life, Safety, Survivability, Risk, Cost and Warranty Claims, pp. 1–11. Barringer & Associates (2004)
Wang, W., Langanke, D.R.: Comparing two designs when the new design has few or no failures—is the new design better than previous one? In: Proceedings - Annual Reliability and Maintainability Symposium, pp. 322–325. IEEE (2001)
Nicholls, D., Lein, P.: Weibayes testing: What is the impact if assumed beta is incorrect? In: 2009 Annual Reliability and Maintainability Symposium, pp. 37–42. IEEE (2009)
Windom, B.C., Sawyer, W.G., Hahn, D.W.: A Raman spectroscopic study of MoS2 and MoO3: applications to tribological systems. Tribol. Lett. 42, 301–310 (2011)
Ferrari, A., Robertson, J.: Interpretation of Raman spectra of disordered and amorphous carbon. Phys. Rev. B. 61, 14095–14107 (2000)
Ferrari, A., Robertson, J.: Resonant Raman spectroscopy of disordered, amorphous, and diamondlike carbon. Phys. Rev. B. 64, 1–13 (2001)
Nakanishi, K., Solomon, P.H.: Infrared absorption spectroscopy. Holden-Day, San Francisco (1977)
Erdemir, A., Ramirez, G., Eryilmaz, O.: In-situ formation of diamond-like carbon boundary films from lubricating oils. In: STLE 1st Tribology Frontiers Conference, Chicago, IL (2014)
Morina, A., Neville, A., Priest, M., Green, J.H.: ZDDP and MoDTC interactions and their effect on tribological performance—tribofilm characteristics and its evolution. Tribol. Lett. 24, 243–256 (2006)
Glover, D.: A ball-rod rolling contact fatigue tester. In: Hoo, J. (ed.) Rolling Contact Fatigue Testing of Bearing Steels, pp. 107–124. American Society for Testing Materials (1982)
Liston, M.: RCF life comparison of bearing steels at two stress levels. Lubr. Eng. 55, 12–19 (1999)
Wei, R., Wilbur, P.J., Kustas, F.M.: a rolling contact fatigue study of hard carbon coated M-50 steel. J. Tribol. 114, 298 (1992)
Rosado, L., Jain, V.K., Trivedi, H.K.: The effect of diamond-like carbon coatings on the rolling fatigue and wear of M50 steel. Wear 212, 1–6 (1997)
Harris, T., Kotzalas, M.N.: Essential concepts of bearing technology. CRC Press, Boca Raton (2007)
De Barros Bouchet, M.I., Martin, J.M., Le-Mogne, T., Vacher, B.: Boundary lubrication mechanisms of carbon coatings by MoDTC and ZDDP additives. Tribol. Int. 38, 257–264 (2005)
Lauer, J.L., Bunting, B.G.: High temperature solid lubrication by catalytically generated carbon. Tribol. Trans. 31, 339–350 (1988)
Blanchet, T.A., Lauer, J.L., Liew, Y.-F., Rhee, S.J., Sawyer, W.G.: Solid lubrication by decomposition of carbon monoxide and other gases. Surf. Coat. Technol. 68–69, 446–452 (1994)
Lauer, J.L., Vlcek, B.L., Sargent, B.L.: Wear reduction by pyrolytic carbon on tribosurfaces. Wear 162–164, 498–507 (1993)
Lauer, J.L., Blanchet, T.A., Vleck, B.L., Sargent, B.L.: Lubrication of Si3N4 and steel rolling and sliding contacts by deposits of pyrolyzed carbonaceous gases. Surf. Coat. Technol. 62, 399–405 (1993)
Evans, R.D., Doll, G.L., Hager, C.H., Howe, J.Y.: Influence of steel type on the propensity for tribochemical wear in boundary lubrication with a wind turbine gear oil. Tribol. Lett. 38, 25–32 (2010)
Benck, J.D., Hellstern, T.R., Kibsgaard, J., Chakthranont, P., Jaramillo, T.F.: Catalyzing the hydrogen evolution reaction (HER) with molybdenum sulfide nanomaterials. ACS Catal. 4, 3957–3971 (2014)
Acknowledgments
The authors are thankful to The Timken Company for providing financial support and guidance. We are grateful for Vanderbilt Chemicals for providing the MoDTC additive. The authors appreciate the help from Dr. P. Shiller for oil and surface analysis in FTIR. We acknowledge Mr. R. Fowler for assistance in depositing the coatings and conducting the tribological experiments.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Mutyala, K.C., Singh, H., Fouts, J.A. et al. Influence of MoS2 on the Rolling Contact Performance of Bearing Steels in Boundary Lubrication: A Different Approach. Tribol Lett 61, 20 (2016). https://doi.org/10.1007/s11249-015-0638-7
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s11249-015-0638-7