从剪切带到地震在一个模型颗粒状材料与接触老化
1Centro Atómico Bariloche, Instituto Balseiro, Comisión Nacional de Energía Atómica, CNEA, CONICET, UNCUYO, Av. E. Bustillo 9500 (R8402AGP), San Carlos de Bariloche, Río Negro, Argentina.
Soft matter
|December 22, 2023
概括
软盘系统中的老化效应会产生一个回入式流动曲线. 这导致了从均变形到剪切带和地震般的棒滑行为,模仿地质断层的现象.
科学领域:
- 软物质物理学 软物质物理学
- 计算材料科学 计算材料科学
- 类风病学 类风病学 类风病学
背景情况:
- 软盘的气流系统在剪切下表现出明显的流动行为.
- 了解粒子间相互作用对宏观性质的影响至关重要.
研究的目的:
- 调查老化影响对多分散软盘系统的质性质的影响.
- 探索从均变形到局部行为在剪切下的过渡.
主要方法:
- 用分子动力学模拟来建模软盘的同质的热气系统.
- 相互作用从纯粹的排斥性变化到包括依赖时间的吸引力,模仿衰老.
主要成果:
- 纯粹的排斥系统显示了一个单调的流动曲线,具有均的变形.
- 引入衰老效应导致了回流流动曲线,导致剪切带局部化.
- 在非常低的应变率下,系统表现出粘滑行为,类似于地震断层活动.
结论:
- 软物质系统中的衰老机制可以诱导复杂的质行为,包括回流流动曲线.
- 模型系统展示了从均流向到局部变形和类似地震的现象的过渡.
- 回流式流量曲线在不同的变形模式中作为一个统一的特征.
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