Study of the morphological and magnetic microstructure of SmCo5 magnets

In this paper, high-coercivity sintered SmCo5 permanent magnets were investigated. The study of the morphological microstructure was performed by scanning electron microscopy (SEM) using backscattered electron imaging and energy dispersive X-ray (EDX) microanalysis, and the magnetic microstructure was observed with magnetic force microscopy (MFM) in the thermally demagnetized state of the magnets at the surface perpendicular to the alignment axis. In addition to the main SmCo5 phase, an appreciable amount of a mixture of the Sm2Co7 and Sm5Co19 phases, pores, Sm oxides and carbon was detected. The grains exhibited magnetic domains. Except for rare cases, the domains were continuous from grain to grain, indicating good magnetic alignment of the individual grains.