相关实验视频
Updated: Jun 10, 2025

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Studying Large Amplitude Oscillatory Shear Response of Soft Materials
Published on: April 25, 2019
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在理论,实验和结构视角下,应力控制的振荡切割下的应力转移:用于探测零切割粘度的应用
Johnny Ching-Wei Lee1, Yu-Tong Hong1, Katie M Weigandt2
1Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801.
概括
这项研究引入了振荡性风湿学测试的新分析,揭示了"应变"现象. 这一发现提供了一种快速的方法来确定零剪切粘度,并有助于理解压力下的材料行为.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物物理 聚合物物理
- 类风病学 类风病学 类风病学
背景情况:
- 振荡性风湿学测量是特征粘弹性质的标准.
- 传统分析提供了对时间和长度尺度的独立控制.
- 现有的方法可能是复杂和耗时的.
研究的目的:
- 为压力控制的振荡性风湿学试验提出一种新的分析方法.
- 在粘弹性材料中引入和验证"应变转移"的概念.
- 开发一种快速的方法来确定零剪切粘度.
主要方法:
- 将振荡测试视为具有暂时变化的应力的爬行测试.
- 分析应力反应相对于应用于应力阶段.
- 使用*in situ*小角度中子散射来观察微观结构的演变.
- 对各种材料进行实验,包括聚合物溶液,凝和化物.
主要成果:
- 在振荡测试中的应变反应呈现出与应用于应力阶段成比例的转移.
- 这种"应变转移"现象在各种粘性弹性材料中观察到.
- 展示了一种新的,高效的方法来确定零剪切粘度.
- 微观结构的方向与可回收的应变相关,独立于应变的变化.
结论:
- 新型变压转移分析提供了一种简化和高效的方法来进行类风学表征.
- 这种方法提供了一个更快的途径来确定关键的材料参数,如零剪切粘度.
- 这些发现对理解材料行为和优化配方有意义.
- 变压转移现象是通用的,适用于时间-温度叠加分析.
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