High-coercivity iron-rich rare-earth permanent magnet material based on (Fe, Co)3B-Nd-M (M=Al, Si, Cu, Ga, Ag, Au)

Publisher Website
Google Scholar
Abstract
High‐coercivity, high‐remanence permanent magnet materials have been obtained via a crystallization treatment of amorphous (Nd,Dy)xFe80.5−x−yCoyB18.5M1 alloys for 3≤x≤5 and 0≤y≤5, where M represent the additives Al, Si, Cu, Ga, Ag, and Au. It has been found that addition of Co and M results in a significant reduction of the crystal grain size and leads to significant improvements both in the intrinsic coercivity and in the energy product. The materials are superior to Nd2Fe14B‐based rapidly solidified materials in the remanence Br, the temperature coefficient of Br, and magnetizability. The typical values of temperature coefficients of Br and HcJ are, respectively, −0.05%/K and −0.35% K. The magnetizing force required to obtain substantial remanence is approximately 0.8 MA/m. Compaction‐molded resin‐bonded magnets produced from these materials have magnetic performance (Br, HcJ) in the range between 0.89 T, 0.29 MA/m and 0.80 T, 0.35 MA/m.