缩进的凝聚性颗粒介质的裂纹图案
Marie-Julie Dalbe1, Pierre Jodlowski1, Nicolas Vandenberghe1
1IRPHE, Centrale Med, CNRS, Aix Marseille Université, Marseille, France.
Physical review. E
|September 16, 2025
概括
这项研究表明,凝聚性颗粒材料,如湿沙,可以在缩时形成裂,类似于易碎的固体. 裂的形成与剪切过程中的材料膨胀有关.
科学领域:
- 地质物理学 地质物理学
- 材料科学 是一种材料科学.
- 固体力学 固体力学是什么
背景情况:
- 凝聚性颗粒材料在屈服之前表现出类似固体的行为.
- 这些材料可能会出乎意料地产生裂,模仿脆性材料的断裂.
- 了解颗粒介质中的裂纹形成对于预测材料故障至关重要.
研究的目的:
- 研究凝聚性颗粒材料的入过程中裂纹形成的机制.
- 描述由此产生的裂纹图案及其与物质行为的关系.
主要方法:
- 湿颗粒介质的准静态入使用固体圆柱形入器.
- 直接观察裂纹的模式.
- 三维X射线微观图谱用于详细的裂特征.
主要成果:
- 观察到辐射裂在缩过程中形成.
- 观察到的裂类似于易碎弹性固体中发现的模式I裂.
- 在剪切和裂纹出现期间的材料膨胀之间建立了直接的相关性.
结论:
- 在特定的负载条件下,凝聚性颗粒材料可以表现出类似脆性的断裂行为.
- 裂的形成与颗粒状材料的扩张反应密切相关.
- 这些发现提供了对颗粒系统中断裂力学的见解.
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