论文标题
部分可观测时空混沌系统的无模型预测
Relaxation dynamics in amorphous alloys under asymmetric cyclic shear deformation
论文作者
论文摘要
使用分子动力学模拟研究了环状载荷和玻璃稳定性对无定形合金中结构弛豫和产量过渡的影响。我们认为，二元混合物深入玻璃相中，并经过循环剪切变形，其中应变会定期变化但保持阳性。我们发现，在不对称循环剪切下，快速冷却的玻璃逐渐向零应变下具有较低势能和有限应力的状态发展。在应变振幅低于临界值的应变幅度下，非承包位移的重新分布会在增加循环数量的情况下，将其重新分布为幂律衰减，指数约为-2。相比之下，在较低应变幅度下，更稳定的玻璃产量的产量，当应变振幅接近临界值时，可以延迟数百个周期的屈服过渡。这些结果对于设计新型热机械加工方法的设计可能很有用，以改善金属玻璃的机械和物理特性。
The influence of cyclic loading and glass stability on structural relaxation and yielding transition in amorphous alloys was investigated using molecular dynamics simulations. We considered a binary mixture cooled deep into the glass phase and subjected to cyclic shear deformation where strain varies periodically but remains positive. We found that rapidly cooled glasses under asymmetric cyclic shear gradually evolve towards states with lower potential energy and finite stress at zero strain. At the strain amplitude just below a critical value, the rescaled distributions of nonaffine displacements converge to a power-law decay with an exponent of about -2 upon increasing number of cycles. By contrast, more stable glasses yield at lower strain amplitudes, and the yielding transition can be delayed for hundreds of cycles when the strain amplitude is near a critical value. These results can be useful for the design of novel thermo-mechanical processing methods to improve mechanical and physical properties of metallic glasses.
