在通用静态机械超材料中的应力指南
1Department of Engineering Mechanics, Center for Nano and Micromechanics and Key Laboratory of Applied Mechanics, Tsinghua University, Beijing 100084, China.
National science review
|August 15, 2024
概括
研究人员开发了一个框架,用于引导机械元材料的静态变形,类似于波导中的波传输. 这使得可控制的应力指南能够用于结构工程和机械计算中的应用.
科学领域:
- 固体力学 固体力学是什么
- 超材料科学科学 超材料科学
- 波浪物理 波浪物理
背景情况:
- 波导中的波束限制促进了定向信号传输,这对于通信和成像至关重要.
- 在机械系统中引导静态变形是具有挑战性的,因为缺陷敏感性.
研究的目的:
- 提出一个一般的框架来表征2D机械元材料中的局部静态变形.
- 为了利用时空二元性来控制静态变形.
- 为了实现应力导体和变形屏蔽等应用.
主要方法:
- 利用静态系统和1D非互惠波系统之间的二元性.
- 通过时空二元性开发内部时间逆对称.
- 通过时间逆向和反向对称度分析等价时间对称度.
主要成果:
- 展示了一种指导准静态负载诱导变形沿指定路径 (应力指导) 的方法.
- 通过打破内部对称性来展示定向变形屏蔽.
- 建立了适用于通用2D静态机械元材料的框架.
结论:
- 开发的框架使得金属材料的可控静态变形成为可能.
- 压力指南在结构任务 (屏蔽,能量收集) 和机械计算方面具有潜力.
- 这项工作将波浪物理概念与静态机械系统联系起来.
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