拉力裂可以破坏经典的速度限制.
Meng Wang1, Songlin Shi1, Jay Fineberg1
1Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904, Israel.
概括
研究人员在易碎的材料中发现超切割裂, 它们比切割波的速度快, 挑战了经典的断裂机制. 这一发现揭示了在关键压力下出现的新材料失效模式.
科学领域:
- 材料科学
- 固体机械学
- 物理
背景情况:
- 通过快速的裂纹扩散来破坏脆弱的材料.
- 经典的断裂力学假设拉力裂的移动速度比雷利波的速度慢.
- 在古典模型中,弹性能量消耗发生在裂尖端.
研究的目的:
- 通过实验证明超切裂纹的存在.
- 调查破裂动态超过剪切波的速度.
- 探索这种非古典断裂模式的基本原则.
主要方法:
- 使用易碎的新胡克材料进行实验.
- 观察和测量裂传播速度.
- 在关键应用应变下分析裂纹动态.
主要成果:
- 实验证据证实超级剪切发生了拉力裂.
- 观察到的裂超过了剪切波速度 ([公式:见文本]).
- 超切裂变的加速速度很平稳, 可能接近扩展波速.
结论:
- 超切断代表了古典裂动态的根本转变.
- 这种非经典的断裂模式是在临界应用于应变时启动的.
- 这些发现挑战了现有的脆性材料故障模型.
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