Universal scaling of the stress-strain curve in amorphous solids
Universal scaling of the stress-strain curve in amorphous solids
复制标题
非晶固体中应力-应变曲线的通用缩放
DOI：
10.1103/physreve.96.033002
复制
发表时间：
2017
影响因子：
2.4
通讯作者：
Zheng Wen
中科院分区：
文献类型：
--
作者：
Lin Jie;Zheng Wen
非晶态固体的屈服相变是一种具有特殊普遍性的相变。临界指数和标度关系已被定义和建议附近的屈服应力。我们在这里表明，即使在剪切的初始阶段远低于屈服应力，应力-应变曲线的非晶固体也显示临界标度与普适指数。其关键是去除应变的弹性部分，剪应力与塑性应变呈现亚线性比例关系。我们展示了这个临界尺度是如何与最小应变的有限尺寸效应相关的，以触发淬火后的第一次塑性雪崩。我们指出，这种次线性的应力和塑性应变之间的标度意味着高阶剪切模量的发散。导出了表征应力-应变曲线和局部稳定性密度分布的两个指数之间的标度关系。我们测试的临界缩放的应力-应变曲线使用介观和原子模拟，并得到令人满意的协议，在二维和三维。
The yielding transition of amorphous solids is a phase transition with a special type of universality. Critical exponents and scaling relations have been defined and proposed near the yield stress. We show here that, even in the initial stage of shear far below the yield stress, the stress-strain curve of amorphous solids also shows critical scaling with universal exponents. The key point is to remove the elastic part of the strain, and the shear stress exhibits a sublinear scaling with the plastic strain. We show how this critical scaling is related to the finite size effect of the minimum strain to trigger the first plastic avalanche after a quench. We point out that this sublinear scaling between the stress and the plastic strain implies the divergence of a high-order shear modulus. A scaling relation is derived between two exponents characterizing the stress-strain curve and the density distribution of the local stabilities, respectively. We test the critical scaling of the stress-strain curve using both mesoscopic and atomistic simulations and get satisfying agreement in two and three dimensions.