Rotational hysteresis in anisotropic barium and strontium ferrite permanent magnets

Abstract

Measurements of the torque curves and rotational hysteresis energies of anisotropic BaFe12O19 and SrFe12O19 permanent magnets have been made at 293, 178, and 77 K. From the values of the rotational hysteresis integrals it has been concluded that magnetization changes occur by an incoherent mechanism, most probably by domain-wall nucleation and displacement.