Critical scaling of icosahedral medium-range order in CuZr metallic glass-forming liquids

Abstract

The temperature evolution of icosahedral medium-range order formed by interpenetrating icosahedra in CuZr metallic glass-forming liquids was investigated via molecular dynamics simulations. Scaling analysis based on percolation theory was employed, and it is found that the size distribution of clusters formed by the central atoms of icosahedra at various temperatures follows a very good scaling law with the cluster number density scaled by $S^{-\tau }$ and the cluster size $S$ scaled by $|1-T_c/T{|}^{-1/\sigma }$, respectively. Here $T_c$ is scaling crossover-temperature. $\tau$ and $\sigma$ are scaling exponents. The critical scaling behaviour suggests that there would be a structural phase transition manifested by percolation of locally favoured structures underlying the glass transition, if the liquid could be cooled slowly enough but without crystallization intervening. Furthermore, it is revealed that when icosahedral short-range order (ISRO) extends to medium-range length scale by connection, the atomic configurations of ISROs will be optimized from distorted ones towards more regular ones gradually, which significantly lowers the energies of ISROs and introduces geometric frustration simultaneously. Both factors make key impacts on the drastic dynamic slowdown of supercooled liquids. Our findings provide direct structure-property relationship for understanding the nature of glass transition.

8 pages, 4 figures; Renamed, Massive Revisions, Scientific Reports Accepted

References in corpus (3)

• Theoretical perspective on the glass transition and amorphous materials
• Roles of icosahedral and crystal-like order in hard spheres glass transition
• A locally preferred structure characterises all dynamical regimes of a supercooled liquid

Cited by in corpus (9)

• Stretched and compressed exponentials in the relaxation dynamics of a metallic glass-forming melt
• Unusual crystallization behavior close to the glass transition
• Classical density functional theory, unconstrained crystallization, and polymorphic behavior
• Can Ordered Precursors Promote the Nucleation of Solid Solutions?
• A Dramatically Growing Shear Rigidity Length Scale in a Supercooled Glass Former ($NiZ{r}_2$)
• Unveiling the early stage evolution of local atomic structures in the crystallization process of a metallic glass
• Al-Cu-Fe alloys: the relationship between the quasicrystal and its melt
• Graph-Dynamics correspondence in metallic glass-forming liquids
• Griffiths-like region explains the dynamic anomaly in metallic glass-forming liquids