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在3D眼镜中的塑料故障之前,负拓电荷的聚类是3D眼镜中的塑料故障
Arabinda Bera1, Matteo Baggioli2,3, Timothy C Petersen4,5
1Department of Physics "A. Pontremoli", University of Milan, Milan 20133, Italy.
PNAS nexus
|September 4, 2024
概括
拓缺陷,如,控制无形固体中的塑性变形. 它们的繁殖和灭绝与物质产量相关,为无形物质行为提供了新的理解.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 类风病学 类风病学 类风病学
背景情况:
- 由于缺乏定义的拓缺陷,在剪切下无形固体的变形机制尚未完全理解.
- 虽然"软点"被用来描述不可逆转的重排,但它们的几何和拓属性仍然不清楚.
研究的目的:
- 在剪切下的3D玻璃模型中识别和描述负责塑料变形的拓缺陷.
- 建立无形材料中的"软点"的几何和拓定义.
主要方法:
- 在剪切变形下的模型玻璃中分析3D非非线位移场.
- 确定和量化状和反状的拓缺陷.
- 缺陷密度,塑性事件和拓电荷之间的相关性分析.
主要成果:
- 在非亲属位移场中发现了类似状和类似状的拓缺陷.
- 缺陷密度和塑性事件之间存在显著的反相关性;缺陷周期与弹性和塑性相相反.
- 在塑性事件期间观察集体缺陷消灭,与负拓电荷集群相关.
结论:
- 拓缺陷为了解无形固体中的"软点"提供了几何和拓框架.
- 这些缺陷起到塑性变形的媒介作用,它们的消灭推动了材料的产量.
- 这些发现为机械理解玻璃材料中的塑料流量铺平了道路.
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