Coercivity of Homogenized Ensembles of Anisotropic γ-Fe_2O_3 Nanoparticles

摘要

The influence of interaction between anisotropic γ-Fe_2O_3 nanoparticles on their coercive force H_c is studied. In samples where the degree of homogenization of anisotropic γ-Fe_2O_3 nanoparticles is high owing to mechanical, ultrasonic, and magnetic dispersion with subsequent filtering of resulting suspensions, H_c is almost independent of volume concentration η of the particles when η varies between 4 × 10~(–4) and 10~(–1). In samples homogenized only mechanically, the H_c versus logη dependence is linear.