Molecular Dynamics Study on Structural Relaxation of Metallic Glasses
Structural relaxation process in the Zr-Cu metallic glasses is investigated by using molecular dynamics simulations. The enthalpy change in isothermal annealing of the glassy state cannot be fitted by a simple exponential function but obeys a stretched exponential function, which indicates that the relaxation in glassy phase is not a single Debye type process. A close examination of individual atomic motion reveals that the enthalpy relaxation is related to a string-like cooperative motion of atoms. The analysis of the local symmetry around each atom shows that a network of the icosahedral clusters grows in the glassy phases during annealing and it closely relates to the free-volume annihilation in the structural relaxation.
T. Chandra, N. Wanderka, W. Reimers , M. Ionescu
M. Shimono and H. Onodera, "Molecular Dynamics Study on Structural Relaxation of Metallic Glasses", Materials Science Forum, Vols. 638-642, pp. 1648-1652, 2010