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Updated: Jun 9, 2025

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Performing Microscope-Mounted Y-Shaped Cutting Tests
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分子损伤在坚固弹性体裂纹启动机制中的作用
Jianzhu Ju1, Gabriel E Sanoja1,2, Luca Cipelletti3,4
1Sciences et Ingénierie de la Matière Molle, CNRS UMR 7615, École supérieure de physique et de chimie industrielles de la Ville de Paris, Sorbonne Université, Paris Sciences et Lettres Université, Paris 75005, France.
概括
多重网络弹性体 (MNE) 显示广泛的分子损伤和非局部应变,延迟骨折. 这项研究揭示了它们的动态断裂机制,用于设计更坚固的材料.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 材料机械学 材料机械学
背景情况:
- 像多重网络弹性体 (MNE) 这样的坚固软材料表现出伸展性和能量消散,抑制裂的生长.
- 现有的骨折模型往往忽略了物质损伤和裂纹尖端附近的局部应力/应变场之间的动态相互作用.
研究的目的:
- 调查裂传播过程中MNE和单网 (SN) 弹性体中的现场分子损伤和变形.
- 开发一个连续模型,将损害分布与裂纹尖端领域结合起来.
- 阐明MNE中的动态断裂机制,以改进材料设计.
主要方法:
- 利用现场空间时间解析的3D测量机械标记的MNE分子损伤.
- 采用数字图像相关性来比较损伤和变形分布.
- 开发并应用了一个连续模型,包括合损伤和裂纹尖端场.
- 在固定手柄放松过程中进行了依赖时间的分子损伤测量.
主要成果:
- 与SN弹性体不同的是,MNE在裂尖之前表现出广泛的,非局部化的分子损伤.
- 与SN弹性体相比,MNE表现出令人惊的非本地化应变度.
- 在MNE中较少局部化的损伤分布被发现延迟了骨折的开始.
- 提出的连续模型成功地解释了观察到的损伤和变形行为.
结论:
- 该研究揭示了MNE的动态骨折机制,突出了广泛损伤和非局部应变的作用.
- 结果为高性能,坚固的弹性体的合理设计提供了关键的见解.
- 了解损伤和变形的结合性质是预测和控制弹性体骨折的关键.
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