Influence of small Cu additions on the microscopical magnetic properties of sintered Nd-Fe-B magnets

摘要

For practical applications of permanent magnets the magnetic energy product, coercivity and rema-nence (also Curie temperature), which are linked to the magnetocrystalline anisotropy, are critical. Sintered magnets based on NdjFeuB have excellent magnetocrystalline anisotropy (1), which can be increased by replacing Nd in the crystal lattice by Dy (2, 3), However, a drawback is that Dy couples anti-parallel to the Fe magnetization and thus reduces the saturation magnetization.