Syntheses And Magnetic Properties Of Nd3co13-Xnixb2 Borides

The effect of substitution of Ni for Co in the borides Nd-3(Co13-xNix)B-2 (x = 0, 1, 2, 3, 4, 5) on the crystal structure and magnetic properties has been investigated. The lattice parameter a decreases while c increases with increasing a: in the range 0 less than or equal to x less than or equal to 5. The Curie temperature and saturation magnetic moment per formula unit in Nd-3(Co13-xNix)B-2 decrease monotonically as the Ni concentration increases. We have observed spin-reorientation transitions at temperatures that decrease monotonically with increasing Ni concentration. It is noteworthy that the substitution of Ni has a significant effect on the magnetocrystalline anisotropy of the Co sublattice, leading to the change of easy magnetization direction of Nd-3(Co13-xNix)B-2 compounds from basal plane to the c axis at room temperature when x less than or equal to 2,The magnetic phase diagram of the Nd-3(Co13-xNix)B-2 borides is given, and the behavior of magnetocrystalline anisotropy is analyzed by the single ion model.