Investigation of crystallization of a mechanically alloyed Sm‐Fe alloy

The crystallization of a mechanically alloyed Sm‐Fe alloy was investigated. The results show that the Sm‐Fe alloy prepared by mechanical alloying consists of amorphous Sm‐Fe phase and crystalline α‐Fe phase. The composition of the alloy is inhomogeneous, i.e., the surface of the as‐milled powder is relatively poor in iron. The crystallization process involves the long‐range diffusion of iron atoms and solid state reaction. After proper crystallization, the as‐milled powder transforms into a Sm2Fe17 phase completely; no distinguishable crystalline α‐Fe phase can be found. A metastable phase, which may be a Sm2Fe17 phase with the structure of hexagonal Th2Ni17 type, appears during the crystallization process.