| 摘要 |
PURPOSE:To obtain the magnet material excellent in all of sintering property, dimensional accuracy and magnetic characteristics by injecting and molding the kneaded material of alnico (aluminum-nickel-cobalt) alloy group permanent- magnet material powder and a binder, removing the binder and sintering a shape. CONSTITUTION:Alloy powder consisting of Al, Ni, Co, Cu, Ti, Nb, V and Fe and the binder consisting of HDPE, APP (high molecular weight) and APP (low molecular weight) are heated and mixed at a ratio of 98:5:9:3, and formed to a columnar shape by a screw type injection molding machine. The shape is degreased through heating, sintered, solution-treated in a magnetic field, quenched and aging-treated for a prolonged time. It is desirable that a plurality of the binders consisting of organic compounds filling the roles of a binder, a slip additive and a plasticizer are prepared, a heating loss curve is measured, and the binders are combined properly. Accordingly, the powder and the binders are mixed so as to be degreased at every approximately fixed quantity to a gradient of a heating temperature. |
