Magnetization reversal behavior and magnetic viscosity of nanocomposite Nd3.6Pr5.4Fe83Co3B5 prepared by melt spinning

Nanocomposite Nd3.6Pr5.4Fe83Co3B5 ribbons were prepared by direct melt spin ning at wheel speed of 20 m/s. Although Nd2Fe14B-type phase and alpha-Fe we re found in the ribbons, a single hard magnetic behavior with high coercivi ty can only be found in the hysteresis loop. The recoil curves show a compa ratively high degree of reversibility in the fields below coercivity. From the investigations of reversible and irreversible portions in DC demagnetiz ation remanence curve, the irreversible nucleation field of about 440 kA/m has been obtained in melt-spun Nd3.6Pr5.4Fe83Co3B5 ribbons. The measurement s of magnetic viscosity show that the time-dependent magnetization changes are associated with reversal of the hard phase. The thermal fluctuation fie ld of about 2.0 kA/m was obtained.