| 摘要 |
PURPOSE:To obtain alloy powder for a magnet having excellent magnetic characteristics by mixing Ca for reducing to a raw material consisting of a heavy rare earth, rare earth, B, Co and Fe, heating the mixture to reduce and diffuse the same then treating the mixture with water. CONSTITUTION:The powder raw material consisting, by atomic %, of 12.5-20% R (where R1; 0.05-5%), 4-20% B, <=35% Co and 45-82% Fe is prepd. R1 is >=1 kinds among Gd, Tb, Dy, Ho, Er, Tm and Yb which are the rare earths and R is R1+R2. R2 is the rare earth element contg. >=80% Nd+Pr and the balance Y except R1. Such powder is mixed with the metallic Ca, etc. at 1.2-3.5 times the stoichiometrically required content and CaCl2 at 1-15wt% of the rare earth (oxide) as the reducing agent. The mixture is reduced and diffused at 950-1,200 deg.C in an inert atmosphere. The resultant product is brought into contact with water to form a slurry. The slurry is further treated with water and the alloy powder of which the main phase is a tetragonal crystal is obtd. The rare earth alloy powder contains <=10,000ppm O, <=1,000ppm C and <=2,000ppm Ca.
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