Permanent magnetic properties of nano-composite Sm2Fe15Si2C/α-Fe with Cu additive

The ribbons of nano-composite Sm2Fe15Si2C/α-Fe with Cu additive were prepared by melt spinning at substrate velocity v=20 m/s. The analysis of x-ray diffraction patterns shows that the relative content of α-Fe phase increases with increasing Fe percent in samples, and the average grain size of 2:17 carbides and α-Fe in the ribbons determined by the Scherrer method is about 50 and 30 nm, respectively. The ribbons exhibit a single hard magnetic phase behavior and remanence enhancement, due to inter-grain exchange coupling between hard and soft magnetic phases. The remanence increases with the increase of iron content in samples, while the coercivity decreases rapidly. The highest maximum energy product around 10.7 MGOe was obtained for Sm8Fe76Cu4Si8C4 ribbons. The reversible and irreversible magnetization portions were analyzed from the recoil loops, and an irreversible nucleation field around 4.8 kOe for hard magnetic phase was observed in Sm8Fe76Cu4Si8C4 ribbons.