rare earth permanent magnet with graded functionality

A functionally graded rare earth permanent magnet is in the form of a sintered magnet body having a composition R 1 a R 2 b T c A d F e O f M g wherein the concentration of R 2 /(R 1 +R 2 ) contained in grain boundaries surrounding primary phase grains of (R 1 , R 2 ) 2 T 14 A tetragonal system within the sintered magnet body is on the average higher than the concentration of R 2 /(R 1 +R 2 ) contained in the primary phase grains, R 2 is distributed such that its concentration increases on the average from the center toward the surface of the magnet body, the oxyfluoride of (R 1 , R 2 ) is present at grain boundaries in a grain boundary region that extends from the magnet body surface to a depth of at least 20 µm, and the magnet body includes a surface layer having a higher coercive force than in the interior. The invention provides permanent magnets having improved heat resistance.