Effect of Dy addition on the magnetic anisotropy of NdFeB alloys

Nd_12.3-xDy_xFe_79.7Nb_0.8Zr_0.8Cu_0.4B₆(x=0,0.5,1.5,2.5) prealloys were annealed for about 10h at high temperature (1 050℃). Then, the NdFeB single-phase alloys were smashed into fine grains and oriented in bonding materials to make them solidified. Magnetization curves in the direction of parallel(//c) and perpendicular(⊥ c) to the magnetic field were measured, and the intersection point of the two curves was considered as magnetic anisotropy. With increasing Dy content, the magnetic anisotropy of the aligned alloys increased distinctly. The maximum magnetic anisotropy was about 7 536 kA·m^-1 obtained at a Dy atomic fraction of 2.5%; with every 1% increase of Dy addition, the anisotropy was elevated about 200——300 kA·m^-1.