[Image credit: Ceglie, et al., JMPS, 2026]

Frictional contact on wavy surfaces [Surface-Topography Challenge Update, May 2026]

Dear STC Community,

Three new updates about the Surface-Topography Challenge.

  • First, this month’s featured investigation: Contact area shrinkage and increase in wavy frictional sliding contacts

    • Marco Ceglie and coworkers looked at friction at soft wavy interfaces using both numerical modeling and experiments (lithographically patterned surfaces).

    • They use the STC paper more for concept than direct application, establishing that real surfaces can be described by a broad spectrum of wavelengths. (They get the award for first citation to the STC paper after it was actually published!)

    • Read the full paper here.

      • (Do you have a paper that cited the STC challenge? Email us to have it featured!)

  • Second, new requesters from 10 different countries. Since the publication of the paper, we’ve had new requests for samples from:

    • Belgium

    • China (multiple)

    • France (multiple)

    • Germany (multiple)

    • Poland

    • Spain

    • Switzerland

    • Turkey

    • United Kingdom

    • USA (many)

    Welcome new requesters!

    • If you are able to report back and/or publish on your results, we hope you will do so!

    • We have participants from manufacturers that say they won’t be able to publish. You are welcome here also; we’re glad you see value in the effort!

  • Third, join us at the Gordon Research Conference in Tribology!

    • ALL of the STC organizers will be attending this year’s GRC in Tribology.

    • Please consider joining us. Apply here.

    • Are you a student or postdoc?

Take care,

Tevis, Arushi, Simeona, Martin, and Lars

Learn more and get in touch at SurfaceTopographyChallenge.org