论文标题
基于Zwanzig-Mountain公式的金属合金中的粘度和脆弱性行为的原子尺度表达式
Atomic-scale expressions for viscosity and fragile-strong behavior in metal alloys based on the Zwanzig-Mountain formula
论文作者
论文摘要
我们使用金属合金的MD模拟的$ G（R）$作为输入的MD模拟，将超冷液体的$ T $依赖性粘度与Zwanzig-Mountain公式结合在一起。该方案导致粘度作为温度的函数的半分析表达，该粘度为粘度的实验数据提供了三参数模型拟合，用于计算$ g（r）$的同一合金。该模型可直接访问原子级物理量的影响，例如原子间潜在$ ϕ（r）$，对粘度和脆弱的行为。特别是，已经确定较陡峭的原子间排斥会导致脆弱的液体，或者相反，“软原子会产生强液”。
We combine the shoving model of $T$-dependent viscosity of supercooled liquids with the Zwanzig-Mountain formula for the high-frequency shear modulus, using the $g(r)$ of MD simulations of metal alloys as the input. This scheme leads to a semi-analytical expression for the viscosity as a function of temperature, which provides a three-parameter model fitting of experimental data of viscosity for the same alloy for which $g(r)$ was calculated. The model provides direct access to the influence of atomic-scale physical quantities such as the interatomic potential $ϕ(r)$, on the viscosity and fragile-strong behavior. In particular, it is established that a steeper interatomic repulsion leads to fragile liquids, or, conversely, that "soft atoms make strong liquids".
