Effect of strain rate on yielding strength of a Zr-based bulk metallic glass

Uniaxial tension and compression experiments were performed on a typical Zr52.5Cu17.9Ni14.6Al10Ti5 (Vit 105) bulk metallic glass over a wide range of strain rates at room temperature. It is found that the strain rate effect of the yielding strength will change from insensitive to negative with increasing strain rate above a critical value. This phenomenon can be quantitatively described by a modified cooperative-shear model of shear transformation zones that takes the adiabatic temperature rise into account. The model predicts well the present and other experimental data.