Nanocrystallization of Ni–Fe–Nb–Si–B amorphous alloys

Four amorphous alloys, NixFe75−xNb3Si9B13 with x=35, 45, 55, 58, were prepared by a melt-quenching technique. The thermal instabilities of the amorphous alloys were studied by using the differential scanning calorimetry (DSC) and the crystallization temperatures have been determined. The crystallization behaviors and the structural characteristics of the alloys were investigated by means of X-ray diffraction experiments. The amorphous alloys were annealed for 30 min at different temperatures: 450, 480, 500, 550, 580 and 600°C, respectively. The crystallization phases were identified and the grain sizes were estimated. The concentration of Ni element in a crystallization phase, γ–(Fe,Ni) solid solution, varied with the alloys. The Ni–Fe–Nb–Si–B alloy with an equal atom percentage of Ni and Fe elements might be a critical composition as the crystallization phases were changed over this composition.