Toward Robust Macroscale Superlubricity on Engineering Steel Substrate

• Published in: Advanced materials (Weinheim) Vol. 32; no. 36; pp. e2002039 - n/a
• Main Authors: Li, Panpan, Ju, Pengfei, Ji, Li, Li, Hongxuan, Liu, Xiaohong, Chen, Lei, Zhou, Huidi, Chen, Jianmin
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01-09-2020
• Subjects: 2D nanomaterials; Coefficient of friction; Engineering; engineering steel substrates; Friction reduction; macroscale; Materials science; Mechanical engineering; Nanocomposites; Robustness; Steel construction; structural superlubricity; Substrates; Tribology; Two dimensional materials
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202002039

“Structural superlubricity” is an important fundamental phenomenon in modern tribology that is expected to greatly diminish friction in mechanical engineering, but now is limited to achieve only at nanoscale and microscale in experiment. A novel principle for broadening the structural superlubricating state based on numberless micro‐contact into macroscale superlubricity is demonstrated. The topography of micro‐asperities on engineering steel substrates is elaborately constructed to divide the macroscale surface contact into microscale point contacts. Then at each contact point, special measures such as pre‐running‐in period and coating heterogeneous covalent/ionic or ionic/ionic nanocomposite of 2D materials are devised to manipulate the interfacial ordered layer‐by‐layer state, weak chemical interaction, and incommensurate configuration, thereby satisfying the prerequisites responsible for structural superlubricity. Finally, the robust superlubricating states on engineering steel–steel macroscale contact pairs are achieved with significantly reduced friction coefficient in 10−3 magnitude, extra‐long antiwear life (more than 1.0 × 106 laps), and good universality to wide range of materials and loads, which can be of significance for the industrialization of “structural superlubricity.”
A novel principle is proposed to assemble numberless “microscale superlubricity” into “macroscale superlubricity,” where the elaborately constructed micro‐asperities of rough engineering substrate play the role of splitting macro‐surface into micro‐points. Then, at each contact point, special measures, such as pre‐running‐in and heterogeneous 2D materials are devised to manipulate the interfacial ordered state, chemical interaction, and incommensurate configuration, thereby achieving robust macroscale superlubricity.