R-FE-B SINTERED MAGNET AND MAKING METHOD

摘要

The invention provides an R-Fe-B sintered magnet consisting essentially of 12-17 at% of Nd, Pr and R, 0.1-3 at% of M 1 , 0.05-0.5 at% of M 2 , 4.8+2*m to 5.9+2*m at% of B, and the balance of Fe, containing R 2 (Fe, (Co)) 14 B intermetallic compound as a main phase, and having a core/shell structure that the main phase is covered with grain boundary phases. The sintered magnet exhibits a coercivity of at least 10 kOe despite a low or nil content of Dy, Tb and Ho.