发表机构
Jawaharlal Nehru Centre for Advanced Scientific Research（贾瓦哈拉尔·尼赫鲁高级科学研究中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究通过原子模拟发现二维玻璃在循环剪切下的疲劳失效时间以指数-1幂律发散，与三维的-2不同，并揭示了损伤累积与失效的稳健联系及失效时间的随机性。
AI 中文摘要
我们利用原子模拟研究了二维（2D）模型玻璃在循环剪切变形下的疲劳破坏。我们发现，当应变振幅趋近疲劳极限时，失效循环次数以幂律形式发散，指数接近$-1$，这与三维（3D）中报道的指数$-2$形成对比。最近也在二维弹塑性模型中观察到失效指数为$-1$，这表明疲劳破坏对空间维度的依赖关系值得深入探讨。累积塑性活动的度量，包括耗散功和非仿射位移，表现出与失效时间的标度关系，这与三维结果一致，并表明损伤累积与失效之间存在稳健的联系。为了探究失效时间变异性的根源，我们进行了等构型“种子”模拟，在其中引入一个局部软区域。虽然这种种子约束了失效的空间位置，但失效时间的分布仍然很宽。这些发现将三维中关于疲劳失效时间的结果扩展到二维玻璃，包括其与累积塑性和表观随机性的关系，同时也揭示了一个关键差异，即描述失效时间发散的指数。
英文摘要
We investigate fatigue failure in two-dimensional (2D) model glasses under cyclic shear deformation using atomistic simulations. We find that the number of cycles to failure diverges as a power law as the strain amplitude approaches the fatigue limit, with an exponent close to $-1$, in contrast to the exponent of $-2$ reported in three dimensions (3D). A failure exponent of $-1$ has also recently been observed in a 2D elastoplastic model, suggesting an interesting dependence on spatial dimensionality that needs to be rationalized. Measures of accumulated plastic activity, including dissipated work and non-affine displacements, exhibit scaling with the failure time that is consistent with results in 3D, and indicate a robust connection between damage accumulation and failure. To probe the origins of the variability of failure times, we perform isoconfigurational {\it seeded} simulations in which a localized soft region is introduced. While such seeding constrains the spatial location of failure, the distribution of failure times remains broad. These findings extend recent results in 3D concerning fatigue failure times to 2D glasses, including their relation to accumulated plasticity and apparent stochasticity, while also revealing a key difference, namely the exponent describing the divergence of the failure times.
