| 摘要 |
PURPOSE:To improve the magnetic properties of a permanent magnet by producing the magnet by resin-bonding method making use of a nucleus alloy of Sm-Pr-Co-Cu-Fe-M system having a specific composition and exhibiting columnar crystalline macrostructure at the time of casting. CONSTITUTION:An alloy is formed mainly of crystals of R2CO17 type (R represents the complex of Sm and Pr) to have Cu, Fe and M (M being at least one of titanium, zirconium, hafnium, vanadium, niobium and tantalum) contents in accordance with atomic ratios as shown by formula. The alloy thus formed is molten in a high-frequency melting furnace within atmosphere of argon gas. The molten metal is then cast by a cylindrical mold to become a cylindrical ingot the cross-section of which includes a region indicated by B in which the macrostructure has columnar crystalline structure. This region B is cut and used as the nucleus alloy. The nucleus alloy having the columnar crystalline structure are resin bonded by means of an epoxy resin to form a permanent magnet. It is thus possible to obtain a permanent magnet having superior magnetic properties and good corner characteristics of hysteresis loop. |
