Patent ID: 8350430

Claim:
An R—Fe—B sintered magnet comprising a rare earth, iron and boron having a structure that includes main phase crystal grains and a grain boundary area surrounding the crystal grains, wherein: the sintered magnet includes fluorine and a specified metal element selected from elements belonging to Group 2 through Group 16 of periodic table excepting the rare earth element, carbon and boron, the fluorine has a concentration that is higher in a region closer to a surface of the magnet than in the center of the magnet, the specified metal element has a concentration which is higher in the region closer to the surface of the magnet than in the center of the magnet, the sintered magnet includes oxyfluoride containing carbon, Dy and the specified metal element in a region of the grain boundary area at a distance of equal to or greater than 1 μm from the surface of the magnet, and the carbon has a concentration that is higher than the concentration of the specified metal element in a region at a distance of from 1 μm to 500 μm from the surface of the magnet.