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arXiv · 1508.03588

Surface Tension regularizes the Crack Singularity of Adhesive Contacts

Stefan Karpitschka·Leen van Wijngaarden·Jacco H. Snoeijer
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Abstract

The elastic and adhesive properties of a solid surface can be quantified by indenting it with a rigid sphere. Indentation tests are classically described by the JKR-law when the solid is very stiff, while recent work highlights the importance of surface tension for exceedingly soft materials. Here we show that surface tension plays a crucial role even for stiff solids: it regularizes the crack-like singularity at the edge of the contact. We find that the edge region exhibits a universal, self-similar structure that emerges from the balance of surface tension and elasticity. The similarity theory provides a complete description for adhesive contacts, reconciling the global adhesion laws and local contact mechanics.

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Stefan Karpitschka, Leen van Wijngaarden, Jacco H. Snoeijer. 2015-08-14. Surface Tension regularizes the Crack Singularity of Adhesive Contacts. https://arxiv.org/abs/1508.03588

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