非互惠和非牛顿力学超材料
Lianchao Wang1,2, Julio A Iglesias Martínez2, Gwenn Ulliac2
1National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, 150001, Harbin, P.R. China.
Nature communications
|August 8, 2023
概括
这项研究设计了一种具有单向抗冲击能力的机械超材料,模仿非牛顿流体行为. 这种新的结构证明了非互惠的反应,克服了被动弹性介质的局限性.
科学领域:
- 固体机械学 固体机械学
- 超材料科学 超材料科学
- 非牛顿动力学的动力学
背景情况:
- 非牛顿式液体表现出取决于速度的反应,与传统材料不同.
- 在被动弹性介质中的互惠性阻碍了声学中的定向反应.
- 理论工作表明,共振准刚体可以使非相互的元材料.
研究的目的:
- 设计一种具有单向抗冲击能力的固体机械超材料.
- 创造一种超越牛顿第二定律的材料,类似于非牛顿流体.
- 实验验证非牛顿和非互惠的弹性行为.
主要方法:
- 对于元材料设计的有限元分析.
- 用于制造的3D打印 (沉积建模和两光子光刻)
- 动态速度依赖的实验来测量弹性响应.
主要成果:
- 成功设计和制造了一种机械超材料.
- 单向抗冲击能力的演示.
- 实验验证取决于速度的非牛顿弹性反应.
- 在冲击逆转时观察内在的非互惠行为.
结论:
- 设计的机械超材料表现出非牛顿弹性特性.
- 该结构实现了单向抗冲击能力,这是一个非互惠的现象.
- 这项工作为开发被动非互惠机械材料提供了一条途径.
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