Structure and crystallization of Fe-B metallic glasses

Abstract

The structure and crystallization of amorphous ${\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{B}}_{x} (0.12<x<0.25)$ alloys have been investigated by M\"ossbauer spectroscopy, differential scanning calorimetry and magnetization measurements. It was found that the first step in crystallization is the precipitation of $\ensuremath{\alpha}$-Fe until the composition of the remaining glass reaches ${\mathrm{Fe}}_{75}$${\mathrm{B}}_{25}$. In the second step this remaining glass transforms into the ${\mathrm{Fe}}_{3}$B intermetallic compound which decomposes at higher temperatures into $\ensuremath{\alpha}$-Fe and ${\mathrm{Fe}}_{2}$B. The results support a quasicrystalline model, where the structure of Fe-B glasses is based on a locally distorted off-stoichiometric ${\mathrm{Fe}}_{3}$B lattice.