Magnetic Properties of Melt-Spun Sm-Fe-Co-B-Si System Alloys

The single-roller method was used to quench by melt spinning Sm-(Fe,Co)-(B,Si) system alloys, and the effects of composition, roller speed and subsequent annealing on the magnetic and other properties were studied. Among other results were that the maximum coercivity was obtained at the composition Sm25Fe71B4, for which i Hc = 3.0 kOe and (BH)max = 6.2 MGOe; that in the vicinity of this composition, the maximum (BH)max and i Hc values were obtained at a roller speed of 11.8 m/s; and that, from X-ray diffraction diagrams, samples showing the highest coercivity consisted of an amorphous phase with a fine crystalline phase intermixed.