Abstract
This paper investigates the underlying mechanisms of Ti and Al doped into ZnO/MoS2 coatings to develop better tribological properties for MoS2-based lubrication coatings. To this end, Ti-ZnO/MoS2 and Al-ZnO/MoS2 coatings with gradient processing were successfully prepared using magnetron co-sputtering with a subsequent annealing treatment. The effects of Ti and Al on the structures and properties of ZnO/MoS2 coatings were analyzed using various analytical methods. The results showed that Ti-ZnO/MoS2 coatings annealed at 300 °C displayed a minimum friction coefficient of 0.07, and Al-ZnO/MoS2 coatings annealed at 300 °C possessed the best oxidation resistance during wear process. Similarly, the highest nano-hardnesses of Ti and Al doped coatings were 1.9 GPa and 2.0 GPa after annealing at 300 °C. The growth of ZnO grains in Ti-ZnO/MoS2 coatings were different from the other coatings based on the Raman analysis, and Al-doped coating showed better fracture toughness and binding forces from indentation and scratch testing. These results suggest that the respective underlying mechanisms of these metals in ZnO/MoS2 coatings were different. As a result, this study shows that select metals could improve the different properties of metal-ZnO/MoS2 coating by utilizing different mechanisms. Formation of ZnS might account for the synergistic lubrication of ZnO and MoS2 co-doped coatings, and ZnO/MoS2 coatings had moisture resistance because of no sulfate radical appeared by XPS analysis. Therefore, metal-ZnO/MoS2 will be potential lubrication coatings to be widely used under natural ambient conditions.
Highlights
MoS2-based solid lubricants have the advantages of a low friction coefficient, high load-bearing capacity, good chemical stability, etc
The results suggest that the power of ZnO target was directly affect on the growth morphology ZnO/MoS2 coatings
The nucleation was repeatedly formed in the first half of the ZnO50 coating growth, and grain growth and epitaxial growth increased with the thicknesses of ZnO/MoS2 coatings
Summary
MoS2-based solid lubricants have the advantages of a low friction coefficient, high load-bearing capacity, good chemical stability, etc. These lubricants are widely used in aerospace, electronics, machinery manufacturing, and other fields.. There is a decrease in wear life, which greatly limits their widely application in real-world To improve these lubricants, several studies have been previously conducted to incorporate dopants into MoS2, including inorganic sulfides, oxides, and metals.. Several studies have been previously conducted to incorporate dopants into MoS2, including inorganic sulfides, oxides, and metals.11–14 Among these dopants, the metal oxides are thermodynamically stable compounds that have been extensively researched, especially for high-temperature applications. The underlying mechanisms of metal doped into ZnO/MoS2 coatings for additional improving lubricating performances were described individually
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.
