| 摘要 |
PURPOSE:To readily obtain an anisotropic permanent magnet having excellent orientation and high magnetic performance (i.e., having no magnetic field restriction) even in a low-magnetic field molding process, by melting a composite resin filled with a magnet powder having uniaxial anisotropy in a cylinder, magnetizing the magnet powder, and injecting and hardening the composite material in a mold cavity to which a magnetic field is applied. CONSTITUTION:A kneaded material obtained by kneading a magnet powder is grounded and formed into pellets so as to be injection-molded easily. The pellets are cast into a cylinder 4 having at its distal end a powder magnetizing circuit constituted by a cylinder coil 1, a ferromagnetic cylinder 2 and an intermediate member 3, and are melted by a heater 5 to obtain a melt 6, which is sent by a screw 7 to the magnetizing circuit to which a magnetic field is applied in the form of pulses. Immediately after the magnet powder has been completely magnetized, the melt 6 is injected into a cavity 11 which is constituted by a mold 8 made of a ferromagnetic material and a mold 9 of a non-magnetic material and to which a magnetic field is applied by a coil 10, and the melt 6 is hardened to obtain an anisotropic permanent magnet 12. Thus, an anisotropic permanent magnet which has excellent orientation and high magnetic performance can be readily obtained at reduced cost even by a low-magnetic field molding process. |
