| 摘要 |
PROBLEM TO BE SOLVED: To satisfy static magnetic characteristics and to improve dispersing property, filling property and oxidation resistance by using metal magnetic powder in a needle or spindle shape, wherein Fe is contained by specified weight% or more, a rear earth element is contained within the range of specified weight% with respect to Fe and the contents of S and Cl are decreased to specified ppm or less. SOLUTION: No.3 sodium silicate is added to the slurry of goethite containing Fe by 50wt.% or more at an axial ratio of 10.4, and pH is adjusted. Thus, SiO2 compound is formed on the surface of particles. After the aqueous solution of hydrate of calcium acetate 1 is added, the aqueous solution of the lanthanum acetate is added so that La/Fe becomes 0.1-5weight%. Furthermore, after the aqueous solution of aluminum nitride is dropped, pH is adjusted, and the compound, whose main component is the hydroxide of La and Al, is formed. Washing is performed by ion exchange water until the contents of S and Cl of the slurry become 200ppm or less. The particles of a metal precursor are aligned. After high-temperature treatment, reduction and surface oxidation are performed. Thus, the metal magnetic powder having the excellent static magnetic property and oxidation resistance and the high filling property is obtained. |
