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Contact Instability in Adhesion and Debonding of Thin Elastic Films

Manoj Gonuguntla·Ashutosh Sharma·Jayati Sarkar·Subash A. Subramanian·Moniraj Ghosh·Vijay Shenoy
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Abstract

Based on experiments and 3-D simulations, we show that a soft elastic film during adhesion and debonding from a rigid flat surface undergoes morphological transitions to pillars, labyrinths and cavities, all of which have the same lateral pattern length scale, close to λ/H ~ 3 for thick films, H > 1 micrometer. The linear stability analysis and experiments show a new thin film regime where λ/H \approx 3+ 2 (γ/3 μH)^(1/4) (γis surface tension, μis shear modulus) because of significant surface energy penalty (for example, λ/H = 6 for H = 200 nm; μ= 1MPa).

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Manoj Gonuguntla, Ashutosh Sharma, Jayati Sarkar, Subash A. Subramanian, Moniraj Ghosh, Vijay Shenoy. 2006-06-27. Contact Instability in Adhesion and Debonding of Thin Elastic Films. https://doi.org/10.1103/physrevlett.97.069903

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