Multimodal Surface Instabilities in Curved Film–Substrate Structures
Structures of thin films bonded on thick substrates are abundant in biological systems and engineering applications. Mismatch strains due to expansion of the films or shrinkage of the substrates can induce various modes of surface instabilities such as wrinkling, creasing, period doubling, folding,...
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| Format: | Article |
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ASME International
2019
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| Online Access: | http://hdl.handle.net/1721.1/120285 https://orcid.org/0000-0002-9292-5267 https://orcid.org/0000-0001-5387-6186 |
| _version_ | 1826199792349347840 |
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| author | Zhao, Ruike Zhao, Xuanhe |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Zhao, Ruike Zhao, Xuanhe |
| author_sort | Zhao, Ruike |
| collection | MIT |
| description | Structures of thin films bonded on thick substrates are abundant in biological systems and engineering applications. Mismatch strains due to expansion of the films or shrinkage of the substrates can induce various modes of surface instabilities such as wrinkling, creasing, period doubling, folding, ridging, and delamination. In many cases, the film-substrate structures are not flat but curved. While it is known that the surface instabilities can be controlled by film-substrate mechanical properties, adhesion and mismatch strain, effects of the structures' curvature on multiple modes of instabilities have not been well understood. In this paper, we provide a systematic study on the formation of multimodal surface instabilities on film-substrate tubular structures with different curvatures through combined theoretical analysis and numerical simulation. We first introduce a method to quantitatively categorize various instability patterns by analyzing their wave frequencies using fast Fourier transform (FFT). We show that the curved film-substrate structures delay the critical mismatch strain for wrinkling when the system modulus ratio between the film and substrate is relatively large, compared with flat ones with otherwise the same properties. In addition, concave structures promote creasing and folding, and suppress ridging. On the contrary, convex structures promote ridging and suppress creasing and folding. A set of phase diagrams are calculated to guide future design and analysis of multimodal surface instabilities in curved structures. Keywords: instability, curvature, film–substrate structure, morphogenesis |
| first_indexed | 2024-09-23T11:25:51Z |
| format | Article |
| id | mit-1721.1/120285 |
| institution | Massachusetts Institute of Technology |
| last_indexed | 2024-09-23T11:25:51Z |
| publishDate | 2019 |
| publisher | ASME International |
| record_format | dspace |
| spelling | mit-1721.1/1202852022-09-27T19:28:54Z Multimodal Surface Instabilities in Curved Film–Substrate Structures Zhao, Ruike Zhao, Xuanhe Massachusetts Institute of Technology. Department of Mechanical Engineering Zhao, Ruike Zhao, Xuanhe Structures of thin films bonded on thick substrates are abundant in biological systems and engineering applications. Mismatch strains due to expansion of the films or shrinkage of the substrates can induce various modes of surface instabilities such as wrinkling, creasing, period doubling, folding, ridging, and delamination. In many cases, the film-substrate structures are not flat but curved. While it is known that the surface instabilities can be controlled by film-substrate mechanical properties, adhesion and mismatch strain, effects of the structures' curvature on multiple modes of instabilities have not been well understood. In this paper, we provide a systematic study on the formation of multimodal surface instabilities on film-substrate tubular structures with different curvatures through combined theoretical analysis and numerical simulation. We first introduce a method to quantitatively categorize various instability patterns by analyzing their wave frequencies using fast Fourier transform (FFT). We show that the curved film-substrate structures delay the critical mismatch strain for wrinkling when the system modulus ratio between the film and substrate is relatively large, compared with flat ones with otherwise the same properties. In addition, concave structures promote creasing and folding, and suppress ridging. On the contrary, convex structures promote ridging and suppress creasing and folding. A set of phase diagrams are calculated to guide future design and analysis of multimodal surface instabilities in curved structures. Keywords: instability, curvature, film–substrate structure, morphogenesis United States. Office of Naval Research (N00014-14-1-0528) Massachusetts Institute of Technology. Institute for Soldier Nanotechnologies National Science Foundation (U.S.) (CMMI1253495) 2019-02-08T15:10:06Z 2019-02-08T15:10:06Z 2017-07 2017-05 2019-01-16T13:22:10Z Article http://purl.org/eprint/type/JournalArticle 0021-8936 1528-9036 http://hdl.handle.net/1721.1/120285 Zhao, Ruike, and Xuanhe Zhao. “Multimodal Surface Instabilities in Curved Film–Substrate Structures.” Journal of Applied Mechanics 84, no. 8 (June 13, 2017): 081001. © 2017 ASME https://orcid.org/0000-0002-9292-5267 https://orcid.org/0000-0001-5387-6186 http://dx.doi.org/10.1115/1.4036940 Journal of Applied Mechanics Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf ASME International ASME |
| spellingShingle | Zhao, Ruike Zhao, Xuanhe Multimodal Surface Instabilities in Curved Film–Substrate Structures |
| title | Multimodal Surface Instabilities in Curved Film–Substrate Structures |
| title_full | Multimodal Surface Instabilities in Curved Film–Substrate Structures |
| title_fullStr | Multimodal Surface Instabilities in Curved Film–Substrate Structures |
| title_full_unstemmed | Multimodal Surface Instabilities in Curved Film–Substrate Structures |
| title_short | Multimodal Surface Instabilities in Curved Film–Substrate Structures |
| title_sort | multimodal surface instabilities in curved film substrate structures |
| url | http://hdl.handle.net/1721.1/120285 https://orcid.org/0000-0002-9292-5267 https://orcid.org/0000-0001-5387-6186 |
| work_keys_str_mv | AT zhaoruike multimodalsurfaceinstabilitiesincurvedfilmsubstratestructures AT zhaoxuanhe multimodalsurfaceinstabilitiesincurvedfilmsubstratestructures |