论文标题
空间相关的旋转动力学揭示了无定形颗粒包装中的应变依赖性
Spatially correlated rotational dynamics reveals strain dependence in amorphous particle packings
论文作者
论文摘要
无定形颗粒包装中的微结构动力学通常是通过量化粒子位移来探测的。虽然当阻碍颗粒的位移时,粒子堆积的刚度会出现,但典型的位移指标如何连接到机械响应并不明显。相比之下,粒子旋转对限制效应的敏感性要差得多,同时仍然对包装的力学敏感。到目前为止,很少有人注意将微观旋转运动与无定形包装的力学联系起来。我们通过实验测量表明,粒子堆积力学可以直接与剪切堆积中的圆形颗粒的旋转运动联系起来。我们的结果表明,旋转动力学的扩散性质高度敏感。另外,旋转动力学存在很大的空间相关性,这是粒子摩擦和堆积密度的函数。对我们的测量分析表明,粒子旋转动力学在无定形材料力学中起着至关重要的作用。
Microstructural dynamics in amorphous particle packings is commonly probed by quantifying particle displacements. While rigidity in particle packings emerges when displacement of particles are hindered, it is not obvious how the typically disordered displacement metrics connect to mechanical response. Particle rotations, in contrast, are much less sensitive to confinement effects, while still sensitive to the mechanics of the packing. So far, little attention has been paid to connect microscopic rotational motion to mechanics of athermal amorphous packings. We demonstrate through experimental measurements that particle packing mechanics can be directly linked to the rotational motion of even round particles in a sheared packing. Our results show that the diffusive nature of rotational dynamics is highly strain sensitive. Additionally, there is substantial spatial correlation in rotation dynamics that is a function of the particle friction and packing density. Analysis of our measurements reveals that particle rotation dynamics plays an essential role in amorphous material mechanics.