Enhancement of magnetic properties by Zn addition in Nd-Fe-B hot-deformed magnets produced by spark plasma sintering method

Nd-Fe-B hot-deformed magnets with Zn addition were prepared from Nd-Fe-B hot-pressed magnets by the spark plasma sintering (SPS) method. The microstructures and magnetic properties of the resultant Nd-Fe-B hot-deformed magnets were investigated. The Nd-Fe-B hot-deformed magnet without Zn addition had the crystallographic alignment of the Nd2Fe14B phase and was magnetically anisotropic, but showed a relatively low coercivity value. It was found that the addition of a small amount of Zn increased the coercivity of the Nd-Fe-B hot-deformed magnets without deteriorating the crystallographic alignment of the Nd2Fe14B phase. The Nd-Fe-B hot-deformed magnet with 1%Zn had fine Nd2Fe14B grains and exhibited a high coercivity of 0.97 MA m−1 with a maximum energy product of 312 kJ m−3.