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在放松软玻璃时异常剪切应力增长
1Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, USA.
Physical review letters
|September 22, 2025
概括
柔软的玻璃状液体记住过去的剪切,显示方向的质签名. 一个新的弹性塑料模型解释了这种记忆效应,没有厚度变异或剪切带,揭示了残留菌株异质变异.
科学领域:
- 软物质物理学 软物质物理学
- 类风病学 类风病学 类风病学
- 材料科学 材料科学 材料科学
背景情况:
- 柔软的玻璃状液体表现出复杂的依赖时间的质行为.
- 过去的剪切历史可以影响当前的流量特性,但潜在的机制仍在争论中.
- 锡克斯托普和剪切带经常被用来解释这些现象.
研究的目的:
- 通过实验证明了在柔软的玻璃状液体中存储定向的学特征.
- 为了在理论上解释这些记忆效应,使用一种新的弹性塑料模型.
- 阐明局部应变状态和异构性在风湿反应中的作用.
主要方法:
- 实验性类风湿测量以探测应力增长和应力后放松的步骤.
- 开发了一种简单的弹性塑料风湿学模型,具有动力定律的产生.
- 在模型中纳入局部菌株状态的分布.
- 理论分析以复制实验观察结果.
主要成果:
- 从过去的剪切历史中存储的定向风湿学特征的实验证据.
- 在小的应变步骤后观察到非单调的压力放松和压力增长.
- 这些反应的理论复制,没有厚度变异或剪切带.
- 作为一个关键机制,确定残留菌株异构性.
结论:
- 柔软的玻璃状液体具有过去变形的记忆,影响它们的质行为.
- 具有局部应变状态的简单弹性塑料模型有效地捕捉了这些记忆效应.
- 剩余应变异性,以不同的速度放松,驱动观察到的应力增加.
- 过去变形对软玻璃材料的影响可能比以前理解的更为深刻.
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