Stretch-induced wrinkling of polyethylene thin sheets: Experiments and modeling

Abstract

a b s t r a c tThis paper presents a study on stretch-induced wrinkling of thin polyethylene sheets when subjected to uniaxial stretch with two clamped ends. Three-dimensional digital image correlation was used to measure the wrinkling deformation. It was observed that the wrinkle amplitude increased as the nominal strain increased up to around 10%, but then decreased at larger strain levels. This behavior is consistent with results of finite element simulations for a hyperelastic thin sheet reported previously (Nayyar et al., 2011). However, wrinkles in the polyethylene sheet were not fully flattened out at large strains (>30%) as predicted for the hyperelastic sheet, but exhibited a residual wrinkle whose amplitude depended on the loading rate. This is attributed to the viscoelastic response of the material. Two different viscoelastic models were adopted in finite element simulations to study the effects of viscoelasticity on wrinkling and to improve the agreement with the experiments, including residual wrinkles and rate dependence. It is found that a parallel network model of nonlinear viscoelasticity is suitable for simulating the constitutive behavior and stretch-induced wrinkling of the polyethylene sheets.

Disappearance of stretch-induced wrinkles of thin sheets: A study of orthotropic films

“…Some other numerical studies [21] also point to such a phenomenon. On the other hand, experimental works lack to confirm this prediction.…”

“…That was a qualitative agreement, a quantitative comparison would be meaningful against simulations of plastic constitutive relations. Such a relation has been published recently [21], however that work completely lacks the investigation of emerging orthotropy during the loading process. This change in the orthotropy parameters is so significant that for some aspect ratios no wrinkling appears at all during the first extension of the specimen, but in the successive cycles it forms repeatedly (watch the video file provided as supplementary data).…”

“…(14). The Euler-Lagrange equations associated with the energy functional in (20) are formally identical to equations (12)(13), nevertheless the stress N is given by (21) in this case.…”

“…50% stretch). Papers in the literature tend to present pure numerical simulations [6,22,20,5,27]; experimental works either aim to incorporate plastic response [30,21] or compare results measured on elastomers against numerical data based on linear elasticity [19]. In accordance with the general expectation, the stretch needed for well developed wrinkled patterns (approx.…”

Wrinkling of extensional thin films through modified large deflection equations analytically and experimentally

“…[20][21][22][23] From the numerous literature survey some related references are illustrated for example. Cerda and Mohadevan proposed a set of simple scaling laws and verified them by elongating polyethylene 26 Taylor et al adopted Koiter's nonlinear plate theory to simulate the wrinkling patterns observed in stretched thin elastic sheets. The numerical solutions to several equilibrium boundary-value problems are obtained and compared with existing experimental, numerical and analytical results.…”