| 摘要 |
PROBLEM TO BE SOLVED: To raise the filling rate of an anisotropic bonded magnet and moreover, to realize the enhancement of the orientational property of the magnet by a method wherein specified wt.% of magnet powder, which satisfies the specified relation between the sizes of a mean crystal grain diameter and a particle diameter, exists and specified wt.% of magnet powder, which satisfies the specified relation between the sizes of a mean crystal grain diameter and a particle diameter, exists. SOLUTION: Leting the mean grain diameter of magnet power be denoted by D and the particle diameter of the magnet powder be denoted by d, 50 wt.% or higher to 80 wt.% or lower of magnet powder, which satisfies the relation of 0.5 D<=d<=1.5 D, exists and 5 wt.% or higher to 20 wt.% or lower of magnet powder, which satisfies the relation of 0.01 D<=d<=0.1 D, exists. In a powder particle diameter which is 1.5 times wider than the mean crystal grain diameter, the orientation of the powder can not be fully performed. Moreover, in a powder particle diameter of 1.2 D or narrower, the powder particle diameter is roughly equal with the mean grain diameter and the direction of easy magnetization of an anisotropic bonded magnet is uniquely determined. When one powder is divided into two, the packing density of the magnet, which was 100% in packing density before the division, is reduced after the division because a gap is surely generated between the two powders. Accordingly, the lower limit of the powder particle diameter is also limited and a powder particle diameter of 0.5 D or wider is batter. |
