3D观测提供了弹性的惊人发现
Zifan Wang1, Shuvrangsu Das1, Akshay Joshi1
1Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, United Kingdom.
概括
在应力下表现出令人惊的局部体积变化,挑战了传统的假设. 这种由移动相驱动的现象,需要对聚合物弹性的修订模型.
科学领域:
- 聚合物物理 聚合物物理
- 材料科学 材料科学 材料科学
- 连续力学 连续力学
背景情况:
- 经典理论假设的弹性仅取决于应变.
- 在负载下聚合物的局部体积变化往往被忽视.
- 了解聚合物变形对于工程应用至关重要.
研究的目的:
- 为了研究和聚合物的局部体积应变.
- 挑战在力学中仅依赖应变的假设.
- 修订弹性的热力学框架.
主要方法:
- 利用先进的X射线测量来捕获3D空间体积力应变场.
- 采用高速放射学来追踪移动阶段的动态.
- 综合实验观测与理论建模.
主要成果:
- 在和常见工程聚合物中显示出显著的局部体积变化.
- 观察到,尽管局部变化,总体样本体积保持不变.
- 确定了一个移动阶段是这些异常行为的原因,包括负局部散装模块.
结论:
- 的机械反应不仅仅是应变的函数.
- 移动相的存在显著影响了聚合物变形.
- 需要修订的热力学模型来准确描述和聚合物弹性.
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