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Updated: May 18, 2026

A Method to Manipulate Surface Tension of a Liquid Metal via Surface Oxidation and Reduction
Published on: January 26, 2016
Mesoscale folding, instability, and disruption of laminar flow in metal surfaces
Narayan K Sundaram1, Yang Guo, Srinivasan Chandrasekar
1Center for Materials Processing and Tribology, Purdue University, West Lafayette, Indiana 47907-2023, USA. nsundara@purdue.edu
Abstract:
Using in situ imaging, we report surface fold formation and fluidlike flow instabilities in sliding of annealed copper. We demonstrate using simulations that folding is principally driven by grain-induced plastic instability. The phenomenon shows remarkable similarities with Kelvin-Helmholtz-type flow instabilities in fluids. While such instabilities have been conjectured to exist in sliding interfaces at the nanoscale, we find vortices and folding in metals at the mesoscale. The occurrence of folds impacts many applications, including surface generation processes and tribology.
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