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Confinement induced instability of thin elastic film

Animangsu Ghatak
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Abstract

A confined incompressible elastic film does not deform uniformly when subjected to adhesive interfacial stresses but with undulations which have a characteristic wavelength scaling linearly with the thickness of the film. In the classical peel geometry, undulations appear along the contact line below a critical film thickness or below a critical curvature of the plate. Perturbation analysis of the stress equilibrium equations shows that for a critically confined film the total excess energy indeed attains a minima for a finite amplitude of the perturbations which grow with further increase in the confinement.

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Animangsu Ghatak. 2005-05-02. Confinement induced instability of thin elastic film. https://doi.org/10.1103/physreve.73.041601

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