PURPOSE: To improve efficiency of formation in a magnetic field of a powder magnetic material and to stabilize quality of a magnet by performing a magnetization treatment as a pretreatment for performing formation in a magnetic field of a powder magnetic material, by forming a spherical aggregate powder having a diameter of a fixed range and by enabling smooth and stable charge for a die to eliminate a fault of finely ground and dried powder in efficiency of formation in a magnetic field due to its poor fluidity for charging a die during formation in a magnetic field of a powder magnetic material.

CONSTITUTION: A powder magnetic material put into a hopper 1 is magnetized by a dc pulse magnetic field when passing through a coil 3, fed into a rotary tube 6 through a chute 5, formed to a spherical aggregate powder of a diameter of 0.3 to 1.2mm of a fixed range through rotation operation controlled by a driving device 7 of a rotary tube and discharged automatically from a discharge part 8.