Synthesis and magnetic properties of Sm5Fe17 hard magnetic phase

It was found that Sm–Fe alloys with the Sm5Fe17 phase can be obtained by annealing of the amorphous melt-spun ribbon. Unlike the Nd5Fe17 phase, the hard magnetic Sm5Fe17 phase was found to be the metastable phase. Thermomagnetic studies revealed the Curie temperature of the Sm5Fe17 phase to be 550 K. The resultant annealed melt-spun ribbon exhibited a large coercivity value of 2.9 MA m−1 at room temperature and 5.0 MA m−1 at 4 K.