Argonne researchers are exploring macroscale superlubricity to reduce and minimize friction. Even a modest 20 percent reduction in friction can significantly affect cost economics in terms of energy savings and environmental benefits.
Macroscopic friction and wear remain the primary modes of mechanical energy dissipation in moving mechanical assembles such as pumps, compressors, turbines etc. leading to unwanted material loss and wasted energy.
We demonstrate our observation of stable macroscale superlubricity while sliding graphene coated surface against diamon-like-coated counterface.
Friction and wear remain as the primary modes of mechanical energy dissipation in moving mechanical assemblies, thus it is desirable to minimize friction in a number of applications. We demonstrate that superlubricity can be realized at engineering scale when graphene is utilized in combination with nanodiamond particles and diamond-like carbon (DLC). Macroscopic superlubricity originates because graphene patches at a sliding interface wrap around nanodiamonds to form nanoscrolls with reduced contact area that slide against the DLC surface, achieving an incommensurate contact and significantly reduced coefficient of friction (~0.004). Atomistic simulations elucidate the overall mechanism and mesoscopic link bridging the nanoscale mechanics and macroscopic experimental observations.
Diana Berman, Sanket A. Deshmukh, Subramanian K. R. S. Sankaranarayanan, Ali Erdemir and Anirudha V. Sumant, “Macroscale Superlubricity Enabled by Graphene Nanoscroll Formation,” Science. DOI: 10.1126/science.1262024, Published Online May 14, 2015.