Al71.25Cu16.15Mg7.6Ni5 amorphous alloy ribbons were prepared using melt-spinning technique. The structure related to the phase transformation of the amorphous alloy ribbon was studied by X-ray diffraction and differential scanning calorimetry (DSC). It was found that the ribbon exhibits two separate diffuse shoulders with peak positions. Formation of cubic-Al was observed when the ribbon was heated beyond the primary crystallization peak. Upon secondary crystallization peak, cubic-Al, Al3Ni and Al2CuMg were observed. The evolution of the lattice constant, a, for the cubic-Al and Al2CuMg, were determined by the Rietveld procedure. The lattice constant for cubic-Al remains almost constant between the primary and fully crystallization temperature after sudden change at secondary crystallization temperature. The lattice constant for Al2CuMg increases when the temperature increases. Both crystallite size of cubic-Al and Al2CuMg were increased as temperature increases.
