| 摘要 |
PURPOSE:To stabilize the dimensions and shape of a sintered cylindrical rare earth magnet and to scarcely generate postcracking of the integrally sintered magnet by inserting a columnar or cylindrical magnetic unit into the inside of the cylindrical molding made in a basic composition of rare earth metal, iron and boron, interposing a metal foil therebetween, and sintering the magnet integrally. CONSTITUTION:A columnar or cylindrical magnetic unit 2 is inserted to the inside of a cylindrical molding 1 made in a basic composition of rare earth metal, iron and boron, a metal foil 3 is interposed therebetween, and sintered to be resultantly integrated. The foil 3 interposed between the molding 1 and the magnetic unit 2 achieves a role of alleviating a distortion due to the difference of thermal expansion coefficient of a cylindrical rare earth element magnet and the columnar or cylindrical magnetic unit 2 due to properties, such as thermal expansion coefficient or ductility thereof and further to melting or softening at the time of cooling after sintering and integrating. Thus, even if the magnet is integrally sintered, it is not cracked. |
