Temperature dependence of the thermoplastic formability in bulk metallic glasses

The temperature dependence of the maximum strain a bulk metallic glass (BMG) can undergo in its supercooled liquid state under specified conditions is determined. This formability is measured experimentally over a wide temperature range using Zr35Ti30Cu8.25Be26.75 as an example BMG. When considering five different BMG formers, we found that the formability continuously increases with temperature. This behavior is ubiquitous among BMGs whose crystallization behavior can be described by steady state nucleation and diffusion limited growth. Therefore, in order to maximize the formability during thermoplastic forming of BMGs, the highest processing temperature should be chosen at which crystallization can still be avoided.