부산대학교 도서관

Commercially used Nd-Fe-B sintered permanent magnets have been widely used in various applications such as hard disc drives, wind power generators, efficient air-conditioner compressors and motors for electric vehicles. Since these applications are often used in high-temprature environments, the required coercivity and remanence have been simultaneously obtained by using the heavy rare earth (HRE) grain boundary diffusion process (GBDP). In this study, we report the heat treatment temperature dependence of magnetic properties as a start to reduce the HRE content of GBDP-based high performance magnets. TbH coated commercial Nd-Fe-B sintered magnets were annealed under various temperatures and the coercivity and remanence were systematically measured. Further description of the microstructure will be discussed in detail.