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自制桥梁的元材料超过了波桑比率的理论极限
Jinhao Zhang1, Mi Xiao2, Liang Gao3
1State Key Laboratory of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, 430074, Wuhan, China.
Nature communications
|July 7, 2023
概括
研究人员开发了新的机械超材料,超越了Poisson比率的热力学极限. 这些材料允许独特的变形模式和非互惠力学,推进软机器人和医疗设备的应用.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 物理 物理学 物理
背景情况:
- 机械超材料以负波桑比率 (氧性) 闻名.
- 现有的波桑比率受到与稳定性,线性和热力学有关的基本界限的约束.
- 克服这些限制可以显著扩大医疗支架和软机器人等领域的应用.
研究的目的:
- 为了证明能够实现Poisson比率超出线性材料的热力学极限的自由形自桥梁元材料.
- 探索这些增强的波桑比率背后的机制及其对物质行为的影响.
主要方法:
- 设计和制造具有多模式微尺度杆的自由形自桥式元材料.
- 使用自接触的桥梁来诱导微尺度杆的多个旋转行为.
- 分析这些微尺度杆行为如何破坏构成张量中的对称性和不变性.
主要成果:
- 实现Poisson比率超出线性材料的热力学极限.
- 一个散装模式的演示,它打破了静态互惠,使得可编程操纵位移场.
- 实现了超大和步态波桑比率,导致双向位移放大和扩张在张力和压缩下.
结论:
- 开发的超材料为机械反应提供了前所未有的控制,超越了传统的限制.
- 这些发现为设计具有可编程非互惠性质的机械系统引入了一个新范式.
- 这项工作为需要异国情调的机械行为的先进应用铺平了道路,例如软机器人和生物医学设备.
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