Mechano‐Activated Shape Morphing of Aluminum–Plastic Laminate Composites
Mechano‐Activated Shape Morphing of Aluminum–Plastic Laminate Composites
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DOI：
10.1002/adem.202301111
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发表时间：
2023-09
影响因子：
3.6
通讯作者：
Chien Nguyen;Karthik Ramalingam;Zachary Kushnir;Fatemeh Rouhani;S. Velankar
中科院分区：
文献类型：
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作者：
Chien Nguyen;Karthik Ramalingam;Zachary Kushnir;Fatemeh Rouhani;S. Velankar
许多“金属化塑料”包装薄膜在拉伸和释放时会弯曲。这种行为可以在通过将铝箔粘合到粘合剂聚合物片材上制备的层压板复合材料中重现。结果表明，这种弯曲的发生是因为拉伸使铝层永久变形（即塑性变形），而聚合物层则是弹性变形。释放后，铝-聚合物复合材料通过弯曲解决了应变不匹配，铝在弯曲的凸侧。曲率随外加应变的增加而线性增加，随铝厚度的增加而减小。考虑应变失配的全弹性双层理论与结果定性一致，但对曲率的预测不足。它显示了如何这样的双层可以与缺陷，如孔或狭缝图案，以实现更复杂的形状变形，以及如何可以实现双向弯曲。这种铝聚合物层状复合材料提供了一种廉价的平台，适用于使用坚固材料的自折叠折纸结构的快速原型设计。
Many “metallized plastic” packaging films bend if stretched and released. Such behavior can be reproduced in laminate composites prepared by bonding aluminum foil to an adhesive polymer sheet. It is shown that such bending occurs because stretching deforms the aluminum layer permanently (i.e., plastically), whereas the polymer layer deforms elastically. Upon releasing, the aluminum–polymer composite then resolves the strain mismatch by bending, with the aluminum on the convex side of the bend. The curvature is found to increase linearly with the applied strain and to reduce as the aluminum thickness increases. The theory of fully elastic bilayers with strain mismatch is in qualitative agreement with the results, but underpredicts the curvatures. It is shown how such bilayers can be patterned with defects such as holes or slits to realize more complex shape morphing, and also how one may achieve bidirectional bending. Such aluminum–polymer‐layered composites provide an inexpensive platform suitable for rapid prototyping of self‐folding origami structures using robust materials.