Structural and magnetic properties of GdCo5-xNix

Abstract

GdCo5 may be considered as two sublattices - one of Gd and one of Co - whose magnetizations are in antiparallel alignment, forming a ferrimagnet. Substitution of nickel in the cobalt sublattice of GdCo5 has been investigated to gain insight into how the magnetic properties of this prototype rare-earth/transition-metal magnet are affected by changes in the transition-metal sublattice. Polycrystalline samples of GdCo5-xNix for 0≤x≤5 were synthesized by arc melting. Structural characterization was carried out by powder x-ray diffraction and optical and scanning electron microscope imagings of metallographic slides, the latter revealing a low concentration of Gd2(Co,Ni)7 lamellae for x≤2.5. Compensation - i.e., the cancellation of the opposing Gd and transition-metal moments - is observed for 1