Magnetic properties and surface domain structure of (Nd0.85Dy0.15)10Fe83Zr1B6 thin ribbons

In this paper, the nanocrystalline (Nd0.85Dy0.15)(10)Fe83Zr1B6 ribbons produced by melt-spinning have been investigated by the X-ray diffraction method (XRD), vibrating sample magnetometer (VSM) and magnetic force microscopy (MFM). The XRD studies showed that material investigated was mainly composed of Re2Fe14B and alpha-Fe phases with fine grain sizes of 25 and 9 nm, respectively. The magnetic parameters determined from the hysteresis loop measurements are as follows: mu H-0(C) = 0.96 T, mu M-0(R) = 0.76 T, mu M-0(S) = 1.09 T, (BH)(max) = 88 kJ/m(3). The large remanence ratio (mu M-0(R)/mu M-0(S)) of 0.7 results from the exchange coupling between the soft and hard magnetic grains. The large surface interaction domains revealed by MFM confirmed the existence of strong exchange coupling between nanosize grains.