论文标题
金属玻璃快速放松的瞬态性质
Transient Nature of Fast Relaxation in Metallic Glass
论文作者
论文摘要
金属玻璃在温度远低于玻璃过渡的温度下表现出快速的机械松弛，其中一种显示几乎没有变化，温度几乎被称为恒定损失（NCL）。尽管这种现象在衰老和变形中具有重要的影响，但放松的起源尚不清楚。通过模型金属玻璃的分子动力学模拟CU_64.5ZR_35.5，我们通过将系统应力分解为原子级应力，以识别负责NCL的原子组。这项工作表明，NCL松弛是由于完全瞬态的原子群在平时时间内正常。它们在整个玻璃上分布在空间上，没有出色的特征，而不是像先前报道的那样类似缺陷。
Metallic glasses exhibit fast mechanical relaxations at temperatures well below the glass transition, one of which shows little variation with temperature known as nearly constant loss (NCL). Despite the important implications of this phenomenon to in aging and deformation, the origin of the relaxation is unclear. Through molecular dynamics simulations of a model metallic glass, Cu_64.5Zr_35.5, we implement dynamic mechanical analysis with system stress decomposed into atomic-level stresses to identify the group of atoms responsible for NCL. This work demonstrates that NCL relaxation is due to fully transient groups of atoms that become normal over picosecond timescales. They are spatially distributed throughout the glass and have no outstanding features, rather than defect-like as previously reported.
