Effect of Humidity on Friction of Molybdenum Disulfide Films Produced by Thermal Evaporation on Titanium Substrates
Chemical Science International Journal,
MoS2 is one of the most advanced solid lubricants that have been used in many machineries. In this work, the effect of humidity on the friction of MoS2 solid film lubricant is investigated using a pin-on-disk tribometer. MoS2 film was coated by a thermal evaporation method on a titanium substrate. Steel and aluminum pins were used for the evaluation of friction coefficient of MoS2 films using a tribometer. The tests showed that with an increase in humidity, the coefficient of friction also increased. In practical applications at high humidity levels, the MoS2 films could be covered by condensed water molecules. Therefore, an experiment to understand the effect of water film on the variation of friction coefficient was also conducted. The results showed that the coefficient of friction remained constant for experiments using both aluminum and steel pins, and then the coefficient of friction increased once the water film was evaporated by the heat generated due to friction. An optical and XRD characterization of the MoS2 film was also conducted.
- Friction coefficient
- humidity effect
- molybdenum disulfide
- thin film.
How to Cite
Singh H, Mutyala KC, Doll GL, Paul A. An improved solid lubricant for Bearings Operating in Space. NASA/CP. 2018;141: 219887.
Zeng XT, He X, Xing-zhao Ding. Tribological properties of Cr- and Ti-doped MoS2 composite coatings under different humidity atmosphere. Surface & Coatings Technology. 2010;205:224.
Chai L, Qiao L, He T, Xu J. Influence of C dopant on the structure, mechanical and tribological properties of r.f.-sputtered MoS2/a-C composite films. Applied Surface Science. 2016;364:249.
Kent A, Forster D, Vortselas A, Buttery M. Hybrid lubrication of PFPE fluids and sputtered MoS2. NASA/CP 2018;151: 219887.
Rohatgi PK, Omrani E, Menezes PL. Self-Lubricating Composites, Germany, Springer-Verlag GmbH; 2018.
Chen J, Zhou H, Ye Y. An investigation of friction and wear performances of bonded molybdenum disulfide solid film lubricants in fretting conditions, Wear. 2009;266: 859.
He T, Yang W, Fu Y, Pang X. Structure, mechanical and tribological properties of MoSN/MoS2 Multilayer Films. Coatings. 2019;9:108.
Zheng S, Liu S, Shang K. Improving the tribological and corrosive properties of MoS2-based coatings by dual-doping and multilayer construction. Applied Surface Science. 2018;437:233.
Sakthivel M, Sudhagar S, Daniel AA. Study on tribological behavior of Al/SiC/MoS2 hybrid metal matrix composites in high temperature environmental condition. Silicon. 2018;10:2129.
Ramanaiah N, Rebbaa B. Evaluation of mechanical properties of aluminum alloy (Al-2024) reinforced with molybdenum disulphide (MoS2) metal matrix composites. Procedia Materials Science. 2014;6:1161.
Klein AN, Furlan KP. Self-lubricating composites containing MoS2: A review. Tribology International. 2018;120:280.
Blau PJ, Watkins T, Qua J. Friction and wear of titanium alloys sliding against metal, polymer, and ceramic counterfaces. Wear. 2005;258:1348.
Ni Y, Gao F, Zhang D. Tribological Performance of polymer composite coatings modified with La2O3 and MoS2 Nanoparticles. J. Tribology. 2019;141: 111601.
Loewenthal SH, Clark CS, Lince JR. Tribological and chemical effects of long-term humid air exposure on sputter-deposited nanocomposite MoS2 coatings. Wear. 2019;432-433:202935.
Hakun C, Cameron Z, Shareef I, Dube M, Krantz T. Performance of MoS2 coated gears exposed to humid air During Storage. NASA/CP. 2018;127:219887.
Jayatissa AH, Schroeder A, Manu BR. Characterization of the effect of moisture on tribology of titanium rubbed against different pin materials. Chemical Science International Journal. 2020;29:1.
Manu BR, Jayatissa AH. Tribological properties at the interface of the aluminum and aluminum oxide. J. Multidisciplinary Engineering Science Studies (JMESS). 2019;5:2594.
Ahmed O, Jayatissa AH. Tribological properties of multilayer TiN and MoS2 Thin Films. Colloid and Surface Science. 2017; 2:137.
Al-Mukhtar AM, Obaidi HA. The frictional coefficient comparison between stainless steel and Beta– Titanium Arch wires ligatured to the stainless-steel bracket Via Different Ligatures. Al – Rafidain Dent J. 2008;8:79.
Szlufarska I, Liu Y. Effect of trace moisture on friction. Appl. Phys. Lett. 2010;96: 101902.
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