English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

At the molecular scale there are strong attractive interactions betweensurfaces, yet few macroscopic surfaces are sticky. Extensive simulations ofcontact by adhesive surfaces with roughness on nanometer to micrometer scalesare used to determine how roughness reduces the area where atoms contact andthus weakens adhesion. The material properties, adhesive strength and roughnessparameters are varied by orders of magnitude. In all cases the area of atomiccontact rises linearly with load, and the prefactor rises linearly withadhesive strength for weak interactions. Above a threshold adhesive strength,the prefactor changes sign, the surfaces become sticky and a finite force isrequired to separate them. A parameter-free analytic theory is presented thatdescribes changes in these numerical results over up to five orders ofmagnitude in load. It relates the threshold strength to roughness and materialproperties, explaining why most macroscopic surfaces do not stick. Thenumerical results are qualitatively and quantitatively inconsistent withclassical theories based on the Greenwood-Williamson approach that neglect therange of adhesion and do not include asperity interactions.

When are rough surfaces sticky?