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Title: Dynamic Behavior of Ribbed Viscoelastic CNT‐PDMS Thin‐Films for Multifunctional Applications
Abstract Tailored ribbing structures are obtained by large‐scale rolling in polymer PDMS thin‐films by adding carbon nanotubes (CNT) inclusions, which significantly improved the mechanical behavior of systems subjected to dynamic compressive strain rates. A nonlinear explicit dynamic three‐dimensional finite‐element (FE) scheme is used to understand and predict the thermomechanical response of the manufactured ribbed thin‐film structures subjected to dynamic in‐plane compressive loading. Representative volume element (RVE) FE models of the ribbed thin‐films are subjected to strain rates as high as 104s−1in both the transverse and parallel ribbing directions. Latin Hypercube Sampling of the microstructural parameters, as informed from experimental observations, provide the microstructurally based RVEs. An interior‐point optimization routine is also employed on a regression model trained from the FE predictions that can be used to design ribbed materials for multifunctional applications. The model verifies that damage can be mitigated in CNT‐PDMS systems subjected to dynamic compressive loading conditions by controlling the ribbing microstructural characteristics, such as the film thickness and the ribbing amplitude and wavelength. This approach provides a framework for designing materials that can be utilized for applications that require high strain rate damage tolerance, drag reduction, antifouling, and superhydrophobicity.  more » « less
Award ID(s):
2031558
PAR ID:
10545836
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Macromolecular Materials and Engineering
ISSN:
1438-7492
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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