在快速移动的裂前沿传播单独的波浪
E Sharon1, G Cohen, J Fineberg
1The Racah Institute of Physics, The Hebrew University of Jerusalem, Givat Ram, Israel.
Nature
|March 10, 2001
概括
新发现的新发现.
科学领域:
- 断裂力学 断裂力学 断裂力学
- 材料科学是一种材料科学.
- 固体机械学 固体机械学
背景情况:
- 易碎材料中的裂通常被简化为2D材料中的1D对象.
- 真正的3D材料呈现出具有单一前线的平面裂纹表面.
- 裂纹前线与不均质相互作用的动力学和形态学尚不清楚.
研究的目的:
- 在3D脆性材料中研究裂纹前线的动态.
- 了解材料不均性对破裂前线行为的作用.
- 解释骨折表面形态的形成.
主要方法:
- 在3D脆性材料中模拟裂前线动态.
- 沿裂纹前线进行波传播的分析.
- 裂纹前端与度的相互作用的检查.
主要成果:
- 扰动会产生长期存在的局部波 ('前线波') 沿裂纹前线传播.
- 前波以大约雷利波速度传播.
- 反传播的前波保持形状和振幅,创建表面痕迹.
结论:
- 前波本质上是3D现象,在2D断裂理论中不存在.
- 前波提供裂与惯性和消散.
- 它们可能会解释与度相互作用时的裂纹连贯性.
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