Mixed viscous flow and softening of bulk metallic glasses

Plastic deformation of Zr 52.5 Ti 5 Cu 17.9 Ni 14.6 Al 10 bulk metallic glass is investigated in a wide range of the strain rates, e, and temperatures, T. Based on these results, a map of the plastic deformation modes as a function of strain rate and temperature is depicted. The region of the mixed flow contiguous to the inhomogeneous plastic deformation region is identified. In this region, at large values of e , the glass softens significantly. This effect is interpreted as a result of the cluster fragmentation.