Introduction and Objectives: In the present study, a detailed study of the structural and phase changes of the Zirconium-based bulk metallic glasses during annealing process and its effect on the mechanical properties has been conducted.
Materials and Methods: In this regard, Zr₆₅Cu₁₅Ti₁₃Ni₇ bulk metallic samples with dimensions of 2×30×30 mm³ were prepared using arc melting followed by injection casting in water-cooled copper mold. The heat treatment process has been done for prepared samples at 250-550 ^oC for 2 h. The resulting structures were examined using field emission scanning electron microscopy, differential thermal analysis, and X-ray diffractometry, and the mechanical behavior was investigated by performing a tensile test using an Instron testing machine.
Results: The results showed heat treatment process at a temperature lower than the glass transition temperature can be effective in improving mechanical properties by increasing the number of shear bands. However, heat treatment at higher temperatures leads to the precipitation of CuZr and Cu₁₀Zr₇ intermetallic compounds, which greatly affect the mechanical properties and lead to a sharp decrease in tensile strength and elongation.
Conclusion: The optimal heat treatment temperature was determined to be 250 °C, which leads to an increase in fracture strength to 1710 MPa and plastic ductility up to 1.65%.