The nanocrystallization of Co67Fe4Cr7Si8B14 Amorphous ribbons which prepared by planar flow melt spinning process (PFMS) was investigated. Crystallization of the ribbons was studied by differential thermal analysis (DTA), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The DTA result of Amorphous ribbon at heating rate of 10oC/min showed occurrence of phase transitions in two stages. The ribbons were isothermally annealed for 30 minutes in argon atmosphere at different temperatures between 300 and 650oC with 25oC steps. The magnetic properties of annealed samples were measured using a vibrating sample magnetometer (VSM). The VSM results revealed that optimum soft magnetic properties occurred at 400oC. XRD patterns showed that the samples isothermally annealed up to 450oC were Amorphous, while TEM results at 400oC indicated 7-8 nm mean size nanocrytallites in Amorphous matrix and size of the nanocrystallites increased by increasing temperature. Also by X-ray diffraction pattern, precipitation of different phases at higher temperatures confirmed.

The crystallization behavior of Ni-Nb Amorphous alloys containing 20, 40 and 60 at.% Nb was studied with a combination of differential scanning calorimetry and x-ray diffractometry. The crystallization sequences were analyzed with regard to the free energy versus composition curves of Ni-Nb system. The crystallization of Ni80Nb20 and Ni40Nb60 Amorphous alloys appeared to occur with a primary crystallization mechanism. Whereas Ni6oNb4oAmorphous alloy crystallized with an eutectic crystallization behavior. The Ni60Nb40 Amorphous alloy was found to be the most stable alloy on heating among three investigated Ni-Nb Amorphous alloys.

In this study, the crystallization behavior of melt-spun Al87Ni10La3 Amorphous phase was investigated by using X-ray diffraction and non-isothermal differential thermal analysis techniques. The results demonstrated that the Amorphous phase exhibited two-stage crystallization on heating, i. e., at first step the Amorphous phase transforms into α-Al phase and at second step Al11La3 and Al3Ni intermetallic phases precipitate, simultaneously. The activation energies of the crystallizations of the Amorphous phase were evaluated by the Kissinger equation using the peak temperature of the exothermic reactions. The values of two-step crystallization activation energies were approximately 173. 7± 6 and 278. 4± 5 kJ/mol, respectively. The Avrami index was calculated for the first and second step of crystallizations and obtained 0. 9 and 3. 8 respectively. This kinetics investigation indicated that in the first step of crystallization of Al87Ni10La3 alloy, the nucleation rate decreases with time, and the crystallization is governed by a three-dimensional diffusion-controlled growth, while the second stage was in interface control regime.