Abstract
Two different greases formulated using MoS2 and a combination of ZDDP and functionalized PTFE (F-PTFE) were examined under spectrum loading conditions where loads, frequency, and duration of the steps were treated as variables. Combination of ZDDP and F-PTFE were synergistic resulting in a significant reduction in the wear and friction under spectrum loading condition. Decreasing the time step during the ramp up and ramp down cycles resulted in larger wear for the grease containing MoS2 particles in comparison to ZDDP/F-PTFE in grease. The tribofilm formed on the surface was analyzed using various characterization techniques like SEM, EDS, and Stereo Optical Microscopy. Tribofilms from MoS2 additives had extensive amounts of abrasive and adhesive wear and showed the formation of MoS2 on the surface on the other hand the tribofilms from ZDDP/F-PTFE had smaller amounts of severe wear and exhibited patchy tribofilms of Zn-phosphates as well as sulfides of Zn and Fe.
Highlights
Greases can be considered as semi-solid lubricants consisting of a thickener material, which is generally a soap that is dispersed in mineral or synthetic oils
The current study was focused on developing an understanding of the role of spectrum loading conditions on the mechanism of wear and friction in greases that contain MoS2 and combinations of
Due to the morphology of the MoS2 particles with sharp edges, they behave as a pro-abrasive agent at lower loads that are not sufficient to overcome Van der Waals forces present at the S-S
Summary
Greases can be considered as semi-solid lubricants consisting of a thickener material, which is generally a soap that is dispersed in mineral or synthetic oils. Greases have gained prominence in the lubricant industry since the onset of the industrial revolution wherein machine parts had to be Lubricants 2015, 3 lubricated and lube oils had limited effectiveness. They are used in applications wherein lube oils cannot stay in place and frequent lubrication is unnecessary. Calcium, and sodium are commonly used as thickeners that form a large entanglement network that is responsible for trapping the oil [1,2,3,4].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
