RFeB-BASED MAGNET PRODUCTION METHOD AND RFeB-BASED SINTERED MAGNETS

文件类型：PDF文档
文件大小：346K
The present invention addresses the problem of providing a production method for RFeB-based sintered magnets having high magnetic properties, manufactured using a grain boundary diffusion method, said RFeB-based sintered magnets having excellent corrosion resistance and little energy loss. A paste (12) is applied to the surfaces of an RFeB-based sinter (11) comprising crystal grains having a main phase of R2Fe14B, which contains a light rare earth element (RL) comprising neodymium and/or praseodymium as a main rare earth element (R). The paste (12) is obtained by mixing a metal powder containing a heavy rare-earth element (RH) comprising at least one of dysprosium, holmium and terbium, with an organic material having an oxygen atom in the molecular structure. A grain boundary diffusion process is then conducted by heating the paste (12) while being brought into contact with the surfaces. A protective layer (13) containing an oxide of the light rare earth element (RL) is thus formed on the surfaces. The protective layer (13) has excellent corrosion resistance and has high electrical resistivity, and therefore suppresses the occurrence of eddy currents during use, contributing to a reduction in energy loss.