Abstract
To develop Nd-Fe-B permanent magnets suitable for radial or circumferential applications, such as a stepping motor, a hot extrusion method was utilized. The extrusion was applied to billets produced by hot-pressing rapidly quenched powder. A planeanisotropic magnet was obtained by forward extrusion and a radial-anisotropic magnet by backward extrusion. The respective magnetic properties of these magnets in the radial direction were as follows: Br=0.895 T, iHc=860 kA/m and (BH)max 134 kJ/m3 for the former, and Br=1.065 T, iHc=520 kA/m and (BH)max=183 kJ/m3 for the latter.
