Wrinkles, folds and ripplocations: unusual deformation structures of confined elastic sheets at non-zero temperatures

Debankur Das; Jürgen Horbach; Peter Sollich; Tanusri Saha-Dasgupta; Surajit Sengupta

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arXiv · 2007.00231

Wrinkles, folds and ripplocations: unusual deformation structures of confined elastic sheets at non-zero temperatures

Debankur Das·Jürgen Horbach·Peter Sollich·Tanusri Saha-Dasgupta·Surajit Sengupta

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Abstract

We study the deformation of a fluctuating crystalline sheet confined between two flat rigid walls as a simple model for layered solids where bonds among atoms {\it within} the same layer are much stronger than those {\it between} layers. When subjected to sufficiently high loads in an appropriate geometry, these solids deform and fail in unconventional ways. Recent experiments suggest that configurations named {\it ripplocations}, where a layer folds backwards over itself, are involved. These structures are distinct and separated by large free energy barriers from smooth {\it ripples} of the atomic layers that are always present at any non-zero temperature. We use Monte Carlo simulation in combination with an umbrella sampling technique to obtain conditions under which such structures form and study their specific experimental signatures.

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Debankur Das, Jürgen Horbach, Peter Sollich, Tanusri Saha-Dasgupta, Surajit Sengupta. 2020-07-01. Wrinkles, folds and ripplocations: unusual deformation structures of confined elastic sheets at non-zero temperatures. https://arxiv.org/abs/2007.00231

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