| 摘要 |
<p>This invention concerns a method of manufacturing plastic bonded magnets and those magnets consist of a generic material, "Lanthanoid", plus yttrium. "Lanthanoid" represents elements 57 to 71 inclusive in the periodic table of elements. The manufacture of those magnets comprises the steps of pulverising the "Lanthanoid" material and aligning the magnetic powder in a magnetic field. The magnetically "Lanthanoid" material is first ground to a powder with a particle site of 1 - 100 .mu., and when the powder is aligned in the magnetic field it is pressed under a pressure of p - 1000 - 10 000 kp/cm2. The "green" body thus obtained is then subjected to heat treatment above the Curie temperature up to a maximum of 1150.degree. in a protective atmosphere for 1 - 20 h, and the resulting body is then infiltrated with plastic in a vacuum of approx. 1 - 30 Toor at a temperature of approx. 20 - 80.degree.C, and the body thus infiltrated is then pressed again in the plastic in liquid form with a pressure of 2 - 2000 kp/cm2. After the plastic is cured the final magnet is machined and then it is magnetised under the influence of a magnetic field.</p> |
