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arXiv · 2606.00626

Sliding contact creates universal self-affine fractal surfaces

Ruibin Xu·Haohao Ren·Adriane Clerc·Guilhem Mollon·Wenbo Sheng·Feng Zhou·B. N. J. Persson
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Abstract

Surface roughness evolves during sliding, a process known as run-in, and the resulting topography controls friction, leakage, and failure from machines to geological faults. Yet the physical rule selecting this state remains unclear. We show that metals, rocks, and glasses develop universal self-similar roughness at short wavelengths, while retaining a material-dependent roll-off. A two-process model explains this behavior: junction formation and rupture drive universal roughening, whereas larger-scale deformation and/or fracture limit its growth.

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Ruibin Xu, Haohao Ren, Adriane Clerc, Guilhem Mollon, Wenbo Sheng, Feng Zhou, B. N. J. Persson. 2026-05-30. Sliding contact creates universal self-affine fractal surfaces. https://arxiv.org/abs/2606.00626

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