The permanent magnet of the permanent magnet and manufacturing method

文件类型：PDF文档
文件大小：1100K
PROBLEM TO BE SOLVED : To solve the problem that when Dy or Tb is diffused in a crystal intergranular phase of a sintered magnet, Dy or Tb reacts with an oxide of an Nd-rich phase if much oxide exists in the Nd-rich phase, resulting in production of many reactive products not contributing to the improvement of magnetic characteristics and prevention of the diffusion of Dy or Tb into the crystal intergranular phase. SOLUTION : A manufacturing method includes a first step of depositing at least one of Dy and Tb on at least part of a surface of an iron-boron-rare earth-based sintered magnet S and a second step of thermally treating at a predetermined temperature to diffuse at least one of Dy and Tb into the crystal intergranular phase of the magnet. In doing so, the sintered magnet with oxygen concentration of 6, 000 ppm or less is used. COPYRIGHT : (C)2008, JPO&INPIT