Nanocrystal Growth in Thermally Treated Fe75Ni2Si8B13C2 Amorphous Alloy

Thermal treatment of amorphous Fe75Ni2Si8B13C2 alloy leads to crystallization of the stable alpha-Fe(Si) and Fe2B as well as to the metastable Fe3B phase. The study of the mechanism of crystal growth of the alpha-Fe(Si) phase revealed that the mechanism of alpha-Fe(Si) growth changes from two dimensional in the early stage to one dimensional in the later stage of crystallization. The Fe2B phase was found to crystallize through two independent routes: from the amorphous phase and from the metastable Fe3B phase, which leads to a different mechanism of crystal growth for each route. Both routes exhibit a change in the mechanism of crystal growth: from two dimensional to one dimensional and from three dimensional to two dimensional, respectively. The respective mechanisms of crystal growth correlate well with the observed changes in preferential orientation of the crystallites of the Fe2B phase.