Optimisation of superplastic processing parameters for (Cu₄₃Zr₄₈Al₉)₉₈Y₂ bulk metallic glasses

In this study, hot compression tests of (Cu₄₃Zr₄₈Al₉)₉₈Y₂ bulk metallic glasses (BMGs) were performed, and their microstructure and thermal properties after the deformation were studied to explore the appropriate range of their optimum processing parameters. The experimental results show that the superplastic deformation of (Cu₄₃Zr₄₈Al₉)₉₈Y₂ bulk metallic glasses depends mainly on the temperature and strain rate. It is suitable for superplastic processing when the alloys are in the state of Newtonian flow and do not crystallise. The appropriate processing parameters of (Cu₄₃Zr₄₈Al₉)₉₈Y₂ BMGs are the temperatures and strain rates, which are below the “dividing line”. And when the temperature is above 733 K, the strain rate must be >1 × 10⁻³ s⁻¹.