| 摘要 |
PURPOSE:To obtain a rare-earth magnet at low cost by a method wherein a didym metal is used as R in the sintered type rare-earth magnet shown by R2T14B. CONSTITUTION:The ingot of (Pr.Nd).Fe.B alloy consisting of 3.3wt% Pr, 30.2 wt% Nd, 1.0wt% B and Fe for the remainder is obtained by performing a high frequency heating on a didym metal (the ratio of Pr and Nd is 1:9, and 98% purity), Fe and B in an argon atmosphere. Then, after said ingot is coarse- pulverized, it is wet-pulverized into the powder having the average grain diameter of approximately 3mum using a ball mill, and then said fine powder is molded in the orthogonal direction with the applied magnetic field of 10kOe by applying the pressure of 1 ton/cm<2>. After said molded body is sintered in Ar at 1,060 deg.C for 2hr, it is cooled slowly at the speed of 100 deg.C/hr or below. The magnetic characteristics of the sintered body obtained as above are almost same as those of the material heretofore in use, but its cost can be reduced to one fifth - one seventh of the conventional magnet. |
