Mechanical properties over the glass transition of Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass

High temperature deformation of a ZrTiCuNiBe bulk metallic glass (BMG) is investigated by compression tests and dynamic mechanical analysis in the supercooled liquid region. The effect of temperature and strain rate on the apparent viscosity is studied. At low strain rates or high temperature, the studied glass exhibits a Newtonian behavior whereas at high strain rates and low temperature, a non-Newtonian behavior is observed. It is shown that the experimental results can be successfully described not only by models frequently used for BMG (stretched exponential function or transition state theory based on a free volume concept) but also by a model initially developed for glassy polymers (based on sheared microdomains). The mechanical response of the investigated BMG is thus compared not only with other BMG but also with amorphous polymers and ceramics.