This work is to investigate the crystallization and its micromechanism for amorphous alloys by means of differential scanning calorimeter (DSC), transmission electron microscopy (TEM), x-ray diffraction (XDF), and in situ TEM observation techniques. A pre-anneal heat treatment was introduced to a melt-spun amorphos Ni-P alloy to change the microstructure of the amorphous samples. By means of systematically kinetic investigation of crystallization processes of the preannealed amorphous samples, variation relationship of the crystallization kinetic parameters with the amorphous microstructure was experimentally demonstrated. The nucleation and growth of nuclei in the crystallization of amorphous Ni P alloy was studied using a concept of "local Avrami exponent", which gives a reasonable interpretation to the crystallization process. According to experimental results of the relationships between local activation energy Ec(x) and the volume fraction transformed x, as well as the n(x)-x relationship, a new method to determine the activation energies for nucleation (En) and growth (Eg) was developed. Variations of En and Eg values with the microstructure of amorphous alloys and the anneal temperatures were confirmed by experimental evidences.
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