A two-sublattice model for extracting rare-earth anisotropy constants from measurements on (Nd,Ce)2(Fe,Co)14B single crystals

Anisotropy constants are obtained from an analysis of single crystal magnetization curves measured up to high fields. The anisotropy of the 3d transition metal sublattice is considered, as well as molecular exchange field coupling between the rare-earth (R) and transition metal sublattices (M). This procedure allows for non colinear R and M magnetic moments, meaning that their angles with respect to the easy axis are independent variables. With this approach we obtain anisotropy constants that are larger than those reported in the literature, which reflects the anisotropy of the isolated R sublattice. Results for Co and/or Ce doped Nd2Fe14B single crystals are presented, showing the influence of such substitutions on the magnetocrystalline anisotropy. These results indicate that the enhanced performance of NdFeB-based magnets co-doped with Ce and Co can be ascribed to an improvement in intrinsic properties.

Automated summary

Anisotropy constants were obtained by analyzing single crystal magnetization curves, taking into account the anisotropy of the 3d transition metal sublattice and the molecular exchange field coupling between rare-earth and transition metal sublattices. The results demonstrated the influence of Co and/or Ce doping on magnetocrystalline anisotropy in Nd2Fe14B single crystals, indicating that co-doping with Ce and Co may improve the performance of NdFeB-based magnets by enhancing intrinsic properties.