Crystallization behavior of amorphous Al84Y9Ni5Co2 alloy

The crystallization behavior and microstructure development upon annealing amorphous Al84Y9Ni5Co2 melt-spun ribbons have been investigated by a combination of differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and X-ray diffraction (XRD). Crystallization is shown to occur in three stages: (1) primary crystallization of α-Al; (2) formation of an unknown crystalline phase; (3) formation of Al3Y, Al9Co2 and a phase similar to Al16Ni3Y. The morphology, EDS and diffraction patterns indicated that the two unknown phases, from the second and third stages, are different phases and both are quaternary compounds.