Characteristics of the glass transition and supercooled liquid state of the Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass - art. no. 052204

Acoustic velocities and their temperature dependence of Zr41Ti14Cu12.5Ni10B e22.5 bulk metallic glass (BMO) have been measured up to 773 K by using an ultrasonic pulse-echo overlap method. The temperature dependence of density , Vicker's hardness, elastic constants, and thermodynamic parameters of the BMG are determined. A rapid change of the density, acoustic velocities, el astic constants, and Debye temperature near the glass transition temperatur e, and anomalous density, acoustic and elastic behaviors in the supercooled liquid region are observed. A striking softening of long-wavelength transv erse acoustic phonons in the glassy state relative to the supercooled liqui d state is found. The glass transition process is delayed to high temperatu re with an increase of heating rate. Our results provide evidence that the glass transition in the BMG can be regarded as a kinetically modified therm odynamic phase transformation.