Magnetic properties of RNi5−xCux intermetallics

The magnetic properties have been studied for the series of RNi5−xCux intermetallics with R=Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Lu; x⩽2.5. Compositional dependences of magnetic susceptibility for the Pauli paramagnets (R=Y, La, Ce, Lu) and the Curie temperature for ferromagnets (R=Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm) have maximum at x=0.2-0.4 and 1, respectively. The substitution of Cu for Ni is accompanied by decreasing spontaneous magnetic moment and increasing coercive force of all ferromagnetic RNi5−xCux but GdNi5−xCux. These results are explained in the frame of band magnetism, random local crystal field, and domain wall pinning theories.