| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic material whose particle orientation effect is recognized, by orienting rare earth-transition metal alloy fine powder whose particle sizes are not more than a specified size in a magnetic field with specified intensity. SOLUTION: In the manufacture method of a magnetic material, the halide of Dy, Sm, Tb, Ho and the like or nitrate is used as rare earth salt and the halide of Fe, Co, Ni and the like, nitrate, and sulfate are used as transition metal salt. The respective water-soluble salts are mixed at a mole ratio at which they become desired alloy compositions and aqueous solution is obtained. Dry coprecipitation fine particles obtained from the mixture aqueous solution is heat-treated, and rare earth and transition metal composite oxide powders are obtained. The composite oxide powders are heat-processed under the existence of reducing agent in inert gas. They are ground to those whose average diameter is not more than 3 μm and they are reduced and dried. Then, rare earth-transition metal alloy fine powders are obtained. The alloy fine powders are stored in a carbon-formed container in a desired form as they are or with epoxy resin. Then, they are formed in the magnetic field of about 0.5-25 kOe and are heat-treated. |
