Onset of irreversibility and chaos in amorphous solids under periodic shear
Onset of irreversibility and chaos in amorphous solids under periodic shear
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DOI：
10.1103/physreve.88.062401
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发表时间：
2013-12-02
影响因子：
2.4
通讯作者：
Reichhardt, Charles
中科院分区：
文献类型：
--
作者：
Regev, Ido;Lookman, Turab;Reichhardt, Charles
非晶材料物理学的一个基本问题是理解从可逆塑性行为到不可逆塑性行为的转变及其与屈服的关系。目前，连续材料建模依赖于唯象屈服阈值，但在许多情况下，从弹性行为到塑性行为的转变是渐进的，这使得很难确定准确的屈服标准。在这里，我们表明，在周期性剪切下，非晶固体随着应变幅度的变化，经历从重复的、可预测的行为到混乱、不规则的行为的转变。在周期性和混沌状态下，都观察到局部粒子重排。我们将从重复行为到混沌行为的转变点与屈服应变联系起来，并表明至少对于振荡剪切，非晶固体的屈服是“向混沌转变”的结果。
A fundamental problem in the physics of amorphous materials is understanding the transition from reversible to irreversible plastic behavior and its connection to yield. Currently, continuum material modeling relies on phenomenological yield thresholds, however in many cases the transition from elastic to plastic behavior is gradual, which makes it difficult to identify an exact yield criterion. Here we show that under periodic shear, amorphous solids undergo a transition from repetitive, predictable behavior to chaotic, irregular behavior as a function of the strain amplitude. In both the periodic and chaotic regimes, localized particle rearrangements are observed. We associate the point of transition from repetitive to chaotic behavior with the yield strain and suggest that at least for oscillatory shear, yield in amorphous solids is a result of a "transition to chaos."