Stability of ZrTiCuNiBe Bulk Metallic Glass upon Isothermal Annealing Near the Glass Transition Temperature

The stability of Zr₄₁Ti₁₄Cu_12.5Ni₁₀Be_22.5 bulk metallic glass (BMG) upon isothermal annealing near the glass transition temperature has been investigated by using x-ray diffraction, differential scanning calorimetry, and the pulse echo overlap method. The density, elastic constants, and thermodynamic parameters as well as their annealing time dependence have been determined. The microstructural and properties changes of the annealed BMG were checked by acoustic measurement. Obvious structural and property changes were observed with prolonged annealing of the BMG near the glass transition temperature.