| 摘要 |
PURPOSE:To easily obtain a specified composition while restraining the fluctuation of rare earth element due to oxidation and evaporation, by performing sintering after ingot wherein the macro structure of alloy practically constituted of rare earth metal and transition metal contains columunar crystal is pulverized, the pulverized magnetic powder is molded in magnetic field, and turned into a preliminary molded object (green body). CONSTITUTION:Alloy is composed of the following; 20-28% rare earth metal such as Y, Sm, Pr, Ce and La, 3-15% Cu, 5-35% Fe, 1-5% one kind or two or more kinds of Zr, Hf, Ti, Nb, Cr, V and Mn, and Co of residual part. This alloy is fused in a high frequency melting furnace and casted in a metal mold. Eighty percent or more of the obtained magnetic alloy ingot is columunar crystal. This alloy is wet-grinded in 'Dyflon(R)' by using a ball mill. Liquid type epoxy resin is added to the fine powder particle, which are blended in a mortar. The fine powder type particle blended with the epoxy resin is subjected to compression molding in a magnetic field press. That is, magnetic field is generated between an exciting coil 1 and a pole piece 2 made of pure ion. The powder blended with the epoxy resin is inserted between an upper punch 3 and a lower punch 4, and oil pressure is applied in magnetic field, thereby performing pressure molding. |
