障碍增强了二维机械元材料的断裂性
Sage Fulco1, Michal K Budzik2, Hongyi Xiao3,4
1Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, PA 19104, USA.
PNAS nexus
|February 10, 2025
概括
机械超材料中的智能障碍通过分配损伤来增强断裂性. 这种效果取决于混乱水平,而不是特定的几何形状,为更强的材料提供了一种新的设计方法.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 固体力学 固体力学是什么
背景情况:
- 机械超材料经常使用复杂的周期几何结构来设计故障特性.
- 达到高断裂性通常涉及与材料强度的权衡.
研究的目的:
- 为了调查障碍在增强机械超材料的断裂性方面的作用.
- 开发一种机械模型,将障碍与性相关联.
- 通过模拟和实验验证模型.
主要方法:
- 用有限元模拟来建模材料的行为.
- 用光弹性实验来可视化故障时的损伤传播.
- 开发了一种新的机械模型,以根据障碍水平来预测性.
主要成果:
- 智能引入混乱导致分布式损伤,增强骨折性.
- 增强性取决于疾病的程度,并确定了最佳水平.
- 开发的机械模型准确地预测了性,并通过模拟和实验验证.
结论:
- 混乱,而不是特定的几何形状,是提高元材料性的关键.
- 一个最佳的障碍水平最大限度地提高了性,超过了有序的对应物.
- 这项研究为设计耐损坏的机械超材料提供了一个新的范式.
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