Crystallization behavior of Ti₄₀Zr₂₅Ni₈ Cu₉Be₁₈ amorphous alloy

Ti-based bulk amorphous alloy with the composition of Ti₄₀Zr₂₅Ni₈ Cu₉Be₁₈ of 3 mm in diameter was fabricated by suction casting method. The microstructure was investigated using X-ray diffraction (XRD), differential scanning calorimetry (DSC) and transmission electron microscopy (TEM). In addition, the crystallization kinetics behavior and phase transition during crystallization process were studied by non-isothermal crystallization and isothermal anneal heat treatment, respectively. It is showed that the glass transition and crystallization behavior have the typical kinetic characteristics and better thermal stability with a supercooled liquid region ΔT_x of 54 K and a phase transformation E_p1 of 213.04 kJ/mol, respectively, for the amorphous alloy. On the other hand, the process of crystallization contained two stages: in the first stage, the crystallization reactions correspond to the precipitation of quasicrystalline phase I in the amorphous matrix; in the second stage, the quasicrystalline phase I was transformed to Laves phase which is directly precipitated from the remaining amorphous matrix.