Fringe instability in constrained soft elastic layers

Shaoting Lin, Tal Cohen, Teng Zhang, Hyunwoo Yuk, Rohan Abeyaratne, Xuanhe Zhao

Research output: Contribution to journalArticle

12 Scopus citations

Abstract

Soft elastic layers with top and bottom surfaces adhered to rigid bodies are abundant in biological organisms and engineering applications. As the rigid bodies are pulled apart, the stressed layer can exhibit various modes of mechanical instabilities. In cases where the layer's thickness is much smaller than its length and width, the dominant modes that have been studied are the cavitation, interfacial and fingering instabilities. Here we report a new mode of instability which emerges if the thickness of the constrained elastic layer is comparable to or smaller than its width. In this case, the middle portion along the layer's thickness elongates nearly uniformly while the constrained fringe portions of the layer deform nonuniformly. When the applied stretch reaches a critical value, the exposed free surfaces of the fringe portions begin to undulate periodically without debonding from the rigid bodies, giving the fringe instability. We use experiments, theory and numerical simulations to quantitatively explain the fringe instability and derive scaling laws for its critical stress, critical strain and wavelength. We show that in a force controlled setting the elastic fingering instability is associated with a snap-through buckling that does not exist for the fringe instability. The discovery of the fringe instability will not only advance the understanding of mechanical instabilities in soft materials but also have implications for biological and engineered adhesives and joints.

Original languageEnglish (US)
Pages (from-to)8899-8906
Number of pages8
JournalSoft Matter
Volume12
Issue number43
DOIs
StatePublished - 2016

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Fringe instability in constrained soft elastic layers'. Together they form a unique fingerprint.

  • Cite this

    Lin, S., Cohen, T., Zhang, T., Yuk, H., Abeyaratne, R., & Zhao, X. (2016). Fringe instability in constrained soft elastic layers. Soft Matter, 12(43), 8899-8906. https://doi.org/10.1039/c6sm01672c