Loading Events

MEAM Seminar: “Tribofilms at the Asperity Scale”

May 15, 2019 at 2:00 PM - 3:00 PM
Details
Date: May 15, 2019
Time: 2:00 PM - 3:00 PM
  • Event Tags:, , ,
  • Organizer
    Mechanical Engineering and Applied Mechanics
    Phone: 215-746-1818
    Venue
    Room 337, Towne Building 220 South 33rd Street
    Philadelphia
    PA 19104
    Google Map

    The presentation will start with an introduction to tribology. This term was first used in a 1965 UK government report which identified the economic loss due to preventable wear and poor friction performance. It helped bring together the diverse community of engineers and scientists that need to collaborate in order to tackle the complex interactions that are central to friction and wear processes. The introduction will conclude with a brief overview of lubricant technology and the associated scope of research themes that support development of new lubricants.

    The core topic will cover recent advances in our understanding of the formation of the lubricant generated boundary or tribofilms that help control friction and wear processes. Our approach has been to develop new methods and tools that allow us to study the interaction of materials, surface morphology, stress and chemical reactivity at the asperity scale within macro scale lubricated rough surface sliding contacts. Highly detailed surface topography, surface elemental analysis and rough surface contact simulation results, obtained from carefully controlled wear experiments, have been mapped onto common asperity scale grids. The results clearly establish that tribofilms initiate very quickly at localized high stress contact spots within the overall macro scale contact footprint. Complementary work in high stress but well separated sliding contacts shows that direct surface contact is not necessarily required to generate surface films. Both sets of experimental results are consistent with stress augmented surface reaction mechanisms that are now being studied by multiple researchers in this field. These developments have shed considerable light on mechanisms that have been elusive for more than 50 years which are key to the performance of lubricants.

    Finally some thoughts on future challenges in tribology and lubrication will be offered. A recent study sponsored by the Society of Tribologists and Lubrication Engineers (STLE) has identified key science and technology, industry, regulatory and global trends that will impact lubrication and tribology. These include increasing electrification of personal vehicles, new and emerging energy sources and the role that tribology plays in enabling new technology development.