On Magnetization Reversal in Hard Magnetic Sm-Fe-N Permanent Magnets

The investigations were carried out on Sm-Fe-N permanent magnets produced by reactive diffusion method. The magnets consist of hard magnetic phases: Sm$\text{}_{2}$Fe$\text{}_{17}$N$\text{}_{0.86}$ and SmFe$\text{}_{5}$ and soft magneticα-Fe phase. From the comparison of experimentally determined angular dependence of coercive field with appropriate theoretical predictions and from the dependence of coercive field on the external magnetic field determined from the minor hysteresis loops, it was stated that magnetization reversal process in Sm-Fe-N magnets is controlled by the nucleation of reversed domains process.