부산대학교 도서관

The microstructural and magnetic properties of melt-spun ribbons with thecomposition (CexNd100-x)30FebalCo4Ga0.2B0.92 (where x = 50, 60, 70, 80, and 90)were investigated. The ribbons were examined with Scanning ElectronMicroscopy (SEM), Transmission Electron Microscopy (TEM), and VibratingSample Magnetometry (VSM). It was found that the grain size of the ribbons ison the nanometer scale, and the grain size decreases with decreasing Ce content. The magnetic hysteresis loops showed that the magnetic properties of theribbons gradually deteriorated with increasing Ce content. This is because themagnetic polarization (Js) and magnetocrystalline anisotropy field (HA) ofCe2Fe14B are smaller than those of Nd2Fe14B. Furthermore, from the initialmagnetization curve it was found that increasing the Ce content changes thecoercive force mechanism to the nucleation mechanism. When Ce contentaccounts for 90% of total rare earth metals, the coercive force mechanismmainly appears to be a nucleation mechanism.