Magnetization reversal processes in sintered permanent magnets Sm(Co, Fe, Zr, Cu)Z

The magnetic hysteresis properties of commercially available samples of sintered permanent magnets with the composition of Sm(Co0.796-xFe0.177CuxZr0.027)(6.63) (x = 0.117 - 0.131) were investigated. To analyze the processes of magnetization and magnetization reversal, the magnetization curves from the thermally demagnetized state, major hysteresis loops, recoil curves, the dependence of the reversible magnetic susceptibility vs. magnetic fields strength, Kelly plots and angular dependences of the coercivity were used. These results indicate that magnetization reversal processes are more complicated than pinning. A model of magnetization reversal processes is proposed to explain why in some experiments the magnets exhibit a pinning mechanism of magnetization reversal and in some experiments a nucleation mechanism.