| 摘要 |
PURPOSE:To obtain a rare-earth cobalt permanent magnet having superior magnetic performance by following method in which Sm quantity in the Sm-Co-Cu- Fe alloy is specially defined, and the ingot is cast to have columnar crystal and then the alloy is magnetized. CONSTITUTION:An alloy composed of Sm2Co17 type crystal mainly, is cast, and Sm2Co17 type crystal contains 21-28wt% Sm in following composition formula i.e. Sm-Co-Cu-Fe-M (M is at least one kind of S, Se, Te, Ce, Pb, Cd and Bi). In the casting process, the chill crystal zone near the mold wall of the ingot is made to become columnar chill crystal, and the crystals in other parts are caused to become columnar crystals, thereby decreasing cubic system crystal of the ingot to the utmost. Next, said alloy is crushed after it is magnetically hardened, and becomes a permanent magnet by combination with resin. By these alloy-composition and columnar crystal structure achieved in casting, the rare earth cobalt permanent magnet having high performance and superior magnetic properties such as coercive force and saturated magnetization etc., is produced. |
