在3D架构材料中解离粒子冲击消散机制
Thomas Butruille1, Joshua C Crone2, Carlos M Portela1,3
1Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139.
概括
超轻的建筑材料在冲击下显示了增强的能量消散. 先进的微尺度测试揭示了建筑特异性对压缩和断裂的抗性,这对于开发新型保护材料至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 纳米技术 纳米技术
背景情况:
- 与散装材料相比,超轻结构材料提供了优越的静态和弹性特性.
- 对于建筑材料在较大的变形下具有动态机械行为的理解有限.
- 现有的表征方法不足以对这些材料进行动态冲击分析.
研究的目的:
- 为3D微型架构材料开发和使用微尺度悬浮板冲击测试框架.
- 在动态冲击条件下量化建筑材料的能耗特性.
- 阐明这些材料中控制能量消散的机制.
主要方法:
- 使用超音速微粒子加速 (高达850m/s) 的微尺度撞击测试框架的开发.
- 超高速成像用于在现场量化撞击能量.
- 尸体鉴定,准静态实验,高保真模拟和维度分析.
主要成果:
- 与单体聚合物相比,建筑材料在质量正常化能耗上显示出47%或更大的增加.
- 确定了两个合的能量消散机制:材料紧缩和粒子诱导的断裂.
- 建筑特有的对压缩和断裂的抗性解释了动态冲击反应的差异.
结论:
- 开发的框架允许对架构材料的动态冲击行为进行定量分析.
- 建筑设计通过受控的紧缩和断裂阻力显著增强动能吸收.
- 这些发现为设计用于保护应用的轻量级,减轻冲击的材料提供了基础.
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