Argonne National Laboratory,
Keywords: Graphene, solid lubricants, crystalline oil
Summary:Every moving mechanical system consisting of contacting/sliding/rotating contacts ranging from micro-machines to large macroscale systems such as wind turbines suffers from the energy loss due to wear and friction and it amounts to roughly a quarter of total energy loss worldwide. We are also faced with an ever-increasing threat to our environment, therefore it is of utmost importance that any new technology that we develop does not negatively impact our environment. In this context, I’ll discuss our research efforts, which are focused on developing oil-free solid lubricant based on atomically thin 2D materials including graphene, and understanding their role at the nanoscale and how it affects reducing friction and wear on the macroscale. I’ll share some fundamental insight about the tribological process involving 2D materials at the sliding interface and how it differs from the conventional thin-film wear process. The fact that these 2D flakes are so thin and mobile at the sliding interface they almost act like a “crystalline oil” providing excellent wear protection as well as easy shearing, which is very distinct from the conventional wear mechanism of thin films coatings. The ability to combine 2D materials with other nanoparticles further boost its ability to generate new lubricant through complex tribochemical reactions at the siding interface providing an almost unlimited supply of the lubricant during the active sliding process. I’ll present our current work on achieving superlubricity in rough steel contacts at high contact pressures as well as at high temperatures and will also touch upon some of the recent work with our collaborators on achieving superlubricity in Mxenes. Finally, I’ll discuss how one can translate these fundamental discoveries into real-world applications by working collaboratively with the industry.