1 School of Material Science and Engineering, Jiangxi University of Science and Technology, Ganzhou 341000 2 Institute of Engineering and Research, Jiangxi University of Science and Technology, Ganzhou 341000
The sintered Nd-Fe-B magnets were fabricated by short-circuit recycling process. The magnetic properties and thermal stability of the magnets with adding PrNd mixed rare earth were also investigated. The magnetic properties of the magnets with 2% PrNd addition were as follows: the remanence (Br) of 1.31 T, the coercivity (Hcj) of 1 474.86 kA/m, and the maximum energy product [(BH)max] of 353.90 kJ/m 3. Compared to the new qualified magnets, the Br, Hcj and (BH)max values of 95%, 102% and 90%, respectively, were recovered. The magnet thermal stability could be improved by PrNd addition. The temperature coefficient of the coercivity reduced from -0.589 9%/K to -0.556 4%/K in the range of 293—393 K. This is mainly because the addition of mixed rare earth PrNd enhances the demagnetization exchange coupling and the magnetocrystalline anisotropy field of the main phase. Thus the coercivity and thermal stability of the magnets are improved.
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2018, Vol. 32 
