Variation of magnetic properties as a function of Mo content in the RFe_12-xMo_x series and their nitrides (R=Y, Nd, Gd)

The structure and magnetic properties of RFe_12-xMo_x series and their nitrides with R=Y,Gd,Nd and x=0.8,1.0,1.5,2.0,2.5 have been studied by x-ray-diffraction and magnetic measurements. It is found that with the increment of Mo content x, the lattice parameters increase, whereas the saturation magnetization, Curie temperature, and anisotropy field decreases in the RFe_12-xMo_x series. Upon nitrogenation lattice parameters, saturation magnetization, and Curie temperature increase. Correspondingly, the easy c-axis magnetocrystalline anisotropy of the Fe sublattice decreases in YFe_12-xMo_xN_y and GdFe_12-xMo_xN_y but increases in NdFe _12-xMo_xN_y although its variation with the Mo content is the same as in their original counterparts. NdFe _12-xMo_xN_y compound in the low Mo content shows great potential for permanent magnet applications.