Crystallization of amorphous Zr60Al15Ni25 alloy

Abstract The phase formation and crystallization kinetics during the thermal treatment of amorphous Zr 60 Al 15 Ni 25 alloy were investigated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). By lowering the isothermal annealing temperatures, it is revealed that the crystallization of the amorphous Zr 60 Al 15 Ni 25 alloy consists of a primary transformation followed by a polymorphic transformation, corresponding to the precipitations of hexagonal Zr 6 Al 2 Ni and the Zr 5 AlNi 4 with a U 3 Si 2 -typed superstructure. The primary phase being Zr 6 Al 2 Ni rather than Zr 5 AlNi 4 in the crystallization is because the latter has a complex structure and its formation requires the diffusion of Al and Zr atoms on a large scale.