Anisotropic Sm2Fe17N3 sintered magnets without coercivity deterioration

In order to solve the problem of coercivity decrease during sintering, we developed a low-oxygen process capable of producing sintered compacts while avoiding oxidization. This study proved that Sm2Fe17N3 sintered compacts produced by the low-oxygen process maintained the coercivity of the raw powder. Scanning transmission electron microscopy observation found no obvious formation of an oxide layer at the sintered interfaces. Magnetic measurements revealed that the coercivity of the sintered magnets decreased as the oxygen concentration increased. In summary, this study demonstrated that Sm2Fe17N3 sintered magnets having the same coercivity as the raw powder can be produced by avoiding oxidization.