NITROGENATION AND SUBSEQUENT SURFACTANT-ASSISTED HIGH ENERGY BALL MILLING OF Sm2Fe17 MELT-SPUN POWDERS

Abstract

Sm 2 Fe 17 melt-spun powders were subjected to the nitriding process and followed by surfactant-assisted high-energy ball milling (HEBM). The microstructures, morphology and magnetic properties were also investigated by X-ray diffractometer, scanning electron microscope and vibrating sample magnetometer. The results showed that the coercivities of the nitrided Sm 2 Fe 17 powders were 1.64 kOe and 3.65 kOe when the nitriding temperatures were 350°C and 450°C, respectively. When the nitriding temperature was 350°C, there was a wasp-shaped hysteresis loop, due to the soft phase of iron, formed during the nitrogenation process. The subsequent surfactant-assisted HEBM can further improve the magnetic properties of the nitrided Sm 2 Fe 17 powders and a 3 h milling process increased the coercivity of the sample nitrided at 450°C reached a high value of 6.97 kOe.