HDDR treated anisotropic Nd-Fe-B powders have been widely used, due to their excellent magnetic
properties, especially for sheet motors and sunroof motors of hybrid and electric vehicles. Final microstructure
and coercivity of such Nd-Fe-B powders depend on the state of starting mother alloys, so additional
homogenization treatment is required for improving magnetic properties of them. In this study, a homogenization
treatment was performed at 900~1140℃ in order to control the grain size and Nd-rich phase distribution, and at
the same time to improve coercivity of the HDDR treated magnetic powders. FE-SEM was used for observing
grain size of the HDDR treated powder and EPMA was employed to observe distribution of Nd-rich phase. Magnetic
properties were analyzed with a vibrating sample magnetometer.