| 摘要 |
PURPOSE:To obtain a magnet suitable to multipolar magnetization by such an arrangement wherein a billet of polycrystalline Mn-Al-C family alloy magnet which has an eaisly magnetizing direction parallel to a specific plane, and is magnetically isotropic within this plane, and also magnetically anisotropic with in such a plane including a direction perpendicular to the plane and a stright line parallel to the specific plane is obtained, and compressive distortion is given to a part of the billet in the direction parallel to the prependicular line. CONSTITUTION:A columnar billet of desired shape is formed by melting and cast ing 69.5wt% Mn, 29.3wt% Al, 0.5wt% C and 0.7wt% Ni. Next, the billet is maintained at 1,100 deg.C for 24hr and then naturally cooled to room temperature and extrusion processed through lubricant and anisotropic magnets are formed by cutting the processed billet into pieces of specified length. After that, the temperature of the magnet is raised to 530-830 deg.C by using a metal mold and then it is plastic processed so that compressive distorition is generated in part of the billet in the direction parallel to the perpendicular line. by this arrangement, a magnet of high performance is obtained by raising the value of its surface magnetic flux higher than that of internal flux. |
