| 摘要 |
PURPOSE:To improve intrinsic coercive force at a room temperature by using elements wherein Dy is excluded and supply amount is large by dispersing V-T-B compound secondary phase. CONSTITUTION:In an Nd-Fe-B system sintered magnet, the temperature coefficient of intrinsic coercive force (iHc) is 0.5%/ deg.C or more. The composition is as follows; R=11-18at% (where R is a rare earth elements except Dy, and 80at% <=(Nd+Pr)/R <=100at%), B=6-12at%, V=2-6at%, residual part Fe, Co (Co is equal to or less than 25at% of the sum of Fe and Co (0% is contained)) and impurity. This V-T-B compound secondary phase (when Fe or Co is contained, T is Fe and Co) is dispersed, and has the maximum energy product larger than or equal to 20 MGOe and the intrinsic coercive force (iHc) larger than or equal to 15 kOe. |
