Crystal structure and its magnetization of rare earth–iron alloys by mechanical alloying

Abstract

In this study, binary mixtures of rare earth–iron powders were prepared by mechanical alloying under argon atmosphere. According to the binary equilibrium phase diagram, solubility of rare earth in iron at room temperature is extremely small. This is because of the existence of that bcc iron equilibrates with the extremely stable intermetallic compounds. In this work, it was found that mechanical alloying drastically increased solubility of rare earth in iron, which is much higher than solubility limits estimated from the equilibrium phase diagram. Furthermore, in this study, it was demonstrated that mechanically alloying production of dominant bcc-phase with amorphous phase at room temperature even at relatively high terbium composition. And their magnetization hystereses were gradually broadened with increasing of rare earth atoms. The coercive force values were almost independent of alloy composition. Especially, the coercive force of terbium–iron powders was drastically increased with increasing terbium concentration. It was suggested that the reason of the above behavior was originated by the existence of rare earth atoms in amorphous phases.