Superlubricity of metal-metal interface enabled by graphene and MoWS4 nanosheets

• Published in: Applied surface science 2020-08, Vol.520, p.146303, Article 146303
• Main Authors: Jiang, Bangzheng, Zhao, Zhicheng, Gong, Zhenbin, Wang, Dailian, Yu, Guoming, Zhang, Junyan
• Format: Article
• Language: English
• Subjects: Graphene; Heterogenous structure; MoWS4; Superlubricity
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2020.146303

[Display omitted] •Macroscale superlubricity in steel-steel interface was realized by MoWS4 + graphene.•We certified that the scrolled tubular structure formed in wear debris.•The incommensurate between tribofilm-nanoscroll-tribofilm, leading to robust superlubricity. Most mechanical parts are made of metal, but the metallic bond has no directivity and the electrons can move freely, resulting in the strong adhesion and high shear force between friction interfaces. Therefore, the existing superlubricity materials almost fail in the metal-metal friction interface. In this work, superlubricity in steel-steel interface was realized by adding MoWS4 + graphene through a simple spray method. MoWS4/graphene nanosheets composite introduced atomic interface mismatch and stimulated the formation of nanoscroll in dry argon. Raman and HRTEM results showed the wear debris had scroll structure and nanostructured tribofilms were generated on the metal surface. As a result, the metal-metal contact was converted into tribofilm-nanoscroll-tribofilm friction couple, providing an incommensurate sliding interface and leading to robust macroscale superlubricity.