Improvement of coervcivity and microstructure of Nd_(14.73)Fe_(78.67)B_(6.60) melt-spun ribbons by addition of Zn

摘要

The microstructures and magnetic properties formelt-spun ribbon of typical composition(Nd_(14.73)Fe_(78.67)B_(6.60))_(100-x) Zn_x (x=0,1,2 and 3)have been studied. We have found that the coercivity was greatlyenhanced and microstructure was sensitively influenced byaddition of Zn. For Nd_(14.73)Fe_(78.67)B_(6.60) magnetswith 1 at% Zn addition, th coercivity at room temperature wasenhanced from 16kOe to 20.2kOe. The highest magneticproperties such as remanence (B_r) coercivity (_iH_c), andmaximum energy product [(BH)_(max)] were 7.54kG, 21kOe,12MGOe, respectively. TEM and EDAX studies revealed thatNd-rich phases were well distiributed along the grain boundariesand Zn concentration is increased around grain boundaries. Inaddition, XRD showed the formation of NdZn_2 phase. Theimprovement of a coercivity by the Zn addition is believed to bedue to good distribution of Nd-rich phase and the appearance of NdZn_2.