The role of Fe3B compound in the crystallization of Fe-B metallic glasses

An amorphous Fe-B system was studied in composition range from 12.5at%B to 24.9at%B by magnetic measurements and Mössbauer spectroscopy. It was found that samples of low B content exhibit crystallization in two stages while in the case of higher B concentration a single stage crystallization occurs. In most cases during the crystallization an intermediate metastable crystalline phase Fe
3
B is formed, which decomposes into α-Fe+Fe
2
B at higher temperatures. The temperature stability of Fe
3
B compound reaches its maximum at about 20% B concentration. A tentative explanation to this experimetal fact is presented.