An anomalous structure disordering in Zr–Cu–Ag supercooled glass-forming liquids

Abstract

An anomalous ordering-to-disordering transition in a Zr–Cu–Ag supercooled glass-forming liquid has been revealed by in situ high-energy x-ray diffraction. Upon heating, the supercooled liquid exhibits a structural crossover at Tc = 716 K, evident by the change in statistical characteristics of the first sharp diffraction peak. When annealed in the vicinity of Tc, the supercooled liquid first relaxes from its initial state to a denser and more ordered state. Subsequently, it becomes disordered at the medium-range scale with a slowing down of densification, as demonstrated by the broadening of the first sharp diffraction peak and a decrease in the peak intensities of the higher atomic shells in the reduced pair distribution function. A scenario for the evolution of less correlated locally favored clusters in the liquid–liquid phase transition is discussed.