The Dependence of Magnetic Properties and Hot Workability of Rare Earth-Iron-Boride Magnets Upon Composition

Hot deformed magnets can be commercially produced from hyper-stoichiometric nanocrystalline Nd-Fe-B compositions. This paper summarizes the influence of the rare-earth component (Nd, Pr, Dy) and gallium to magnetic properties and hot workability of die-upset magnets based upon hyper-stoichiometric compositions. Increasing the Nd from 13.3 to 14.4 at.% raises the H/sub ci/ from 770 to 930 kAm/sup -1/. B/sub r/ values are highest (1.31 T) at lower levels of RE (/spl sim/13 at.%), although such compositions exhibit a decrease in hot workability. The substitution of Dy and Pr for Nd promotes higher H/sub ci/ values at some expense in B/sub r/. Gallium additions up to 0.5 at.% significantly increase both B/sub r/ and H/sub ci/.