周期剪切对二元玻璃结构弛豫和孔再分布的影响
The influence of periodic shear on structural relaxation and pore redistribution in binary glasses
摘要:
采用分子动力学模拟研究了二元玻璃在振荡剪切变形下的孔结构、势能和局域密度的演化。多孔玻璃最初通过从液态跨越玻璃化转变的快速热淬火来制备,并允许相分离和在恒定体积下固化,从而在非晶态固体中产生扩展的多孔网络。我们发现,在周期性剪切下,由于玻璃质材料的逐渐重排,势能在连续的循环中降低,并且在较大的应变振幅下,数千次剪切循环后的势能的最小值较低。此外,随着循环次数的增加,孔径分布变得更加偏向于更大的长度尺度,在更大的应变幅下,开发出明显的峰,并且峰强度增强。局部密度分布函数的数值分析表明,循环加载导致形成更高密度的固体域和玻璃相的均匀化与降低密度。
英文摘要:
The evolution of porous structure, potential energy and local density in binary glasses under oscillatory shear deformation is investigated using molecular dynamics simulations. The porous glasses were initially prepared via a rapid thermal quench from the liquid state across the glass transition and allowed to phase separate and solidify at constant volume, thus producing an extended porous network in an amorphous solid. We find that under periodic shear, the potential energy decreases over consecutive cycles due to gradual rearrangement of the glassy material, and the minimum of the potential energy after thousands of shear cycles is lower at larger strain amplitudes. Moreover, with increasing cycle number, the pore size distributions become more skewed toward larger length scales where a distinct peak is developed and the peak intensity is enhanced at larger strain amplitudes. The numerical analysis of the local density distribution functions demonstrates that cyclic loading leads to formation of higher density solid domains and homogenization of the glass phase with reduced density.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。