Fe–B ultrafine amorphous alloy particles (UFAAP) were prepared by chemical reduction of Fe3+ with NaBHO4 and confirmed to be ultrafine amorphous particles by transmission electron microscopy and X-ray diffraction. The specific
heat of the sample was measured by a high precision adiabatic calorimeter, and a differential scanning calorimeter was used
for thermal stability analysis. A topological structure of Fe-B atoms is proposed to explain two crystallization peaks and
a melting peak observed at T=600, 868 and 1645 K, respectively.