建筑2D格子材料的意想不到的曲行为
Yu Yao1, Yong Ni1, Linghui He1
1CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China, Hefei, Anhui 230026, China.
Science advances
|June 21, 2023
概括
架构的2D格子材料显示可调节的Poisson比率. 与普遍认为的相反,它们的曲曲率取决于梁面比,而不仅仅是Poisson的比率,使新的形状变化设计.
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:
- 架构的二维 (2D) 格子材料提供可调节的波桑比率.
- 一个普遍的假设是,在曲过程中,正的Poisson比率与反弹性曲率和负的比率与同弹性曲率之间存在联系.
研究的目的:
- 为了研究2D格子材料中Poisson比率和曲曲率之间的关系.
- 挑战建筑材料中曲率行为的传统理解.
主要方法:
- 具有星形单元细胞的二维格子的理论分析.
- 理论预测的实验验证.
- 使用Cosserat连续性方法进行建模.
主要成果:
- 在2D网格中观察到反克拉斯和同克拉斯曲曲线之间的过渡.
- 这种过渡可以通过光束的截面比来控制,独立于固定的波松比.
- 底层机制涉及轴向扭转和外平面光束曲的相互作用.
结论:
- 关于二维网格中的波桑比率和曲曲率的普遍信念并不普遍.
- 梁面比显著影响曲率,提供新的设计参数.
- 结果为设计2D格子系统提供了深入的见解,用于先进的形状转换应用.
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