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

In this paper, the nanocrystalline (Nd0.85Dy0.15)10Fe83Zr1B6 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 α-Fe phases with fine grain sizes of 25 and 9 nm, respectively. The magnetic parameters determined from the hysteresis loop measurements are as follows: μ0HC = 0.96 T, μ0MR = 0.76 T, μ0MS = 1.09 T, (BH)max = 88 kJ/m3. The large remanence ratio (μ0MR/μ0MS) 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.