| 摘要 |
PURPOSE:To obtain the alloy powder having low contents of alkali (earth) metal and chlorine and appropriate for an alloying target for magnetic recording by using calcium oxide as the disintegration accelerator in the production of the powder by the reductive diffusion method. CONSTITUTION:One or more kinds of reducing agents among alkali (earth) metals, their hydrides and calcium oxide are added to the mixed powder of Tb oxide and transition metals contg. >=1 kind among iron, Ni and Co. The mixture is heated in an inert gas atmosphere or in vacuum to obtain a lumpy reaction product mixture. When the mixture is brought into contact with water, the unreacted reducing agent in the mixture, the by-produced oxides of the reducing agent, etc., are dissolved as the hydroxides, and the lumpy mixture is disintegrated. The formed slurry is agitated, and the hydroxides are removed from the obtained alloy powder by decantation. Meanwhile, metallic Ca is appropriately used as the reducing agent from the standpoint of handling and cost. Although the reducing agent is formed from the metallic Ca, the amt. is insufficient to accelerate disintegration. |
