Stability and crystallization of Fe81B13Si4C2 amorphous alloy

The thermal stability and crystallization of the Fe81B13Si4C2 amorphous alloy were investigated in the temperature range of 300–1173 K. The correlation of the DSC and X-ray diffraction data with the measurements of electric and magnetic properties, which are very sensitive to structural changes, has shown a complex crystallization process involving at least two overlapping steps which appeared as one sharp slightly asymmetrical crystallization peak on the DSC curve. That could mean that the entire nucleation process did not take place during the early stage of the transformation and did not become negligible afterward. In this case, the crystallization rate is not defined by only the temperature but also depends on the previous thermal history of the alloy. This could be reason why the Johnson–Mehl–Avrami model usually used for the description of crystallization involving the stage of nucleation and the stage of growth of nuclei is not valid.