Determining the material time of an aging metallic glass - relation of dynamics and structure

Glasses are off-equilibrium materials that slowly relax towards their meta-stable equilibrium state, which is referred to as physical aging. Physical aging is known to be a highly non-linear process with regard to temperature history. The physical origin of this non-linearity has been proposed decades ago within the famous material time concept. Recently, this conjecture has been confirmed by some of the authors for an aging molecular glass, by the first-time experimental determination of the material time, which was then shown to, e.g., linearize the change of the material's dielectric properties during aging. The proposal aims to extend the material time concept to metallic glasses, by XPCS experiments. Moreover, simultaneous structural characterizations offer the unique opportunity of verifying whether the material time, determined from dynamical properties of the material, does linearize the change of the material's structure during aging.