Structure and Magnetic Properties of Mechanically Alloyed Ferrite Nanopowders

The morphology and magnetic characteristics of mechanically alloyed magnetite and cobalt and magnesium spinel-ferrite nanopowders are investigated in this study. The objective is to analyze the impact of nanopowder particle size on the saturation magnetization and the roles of surface anisotropy and magnetoelastic energy in magnetic anisotropy formation through a core-shell model. Methodology includes the systematic evaluation of the nanopowder characteristics and their biological compatibility for future medical technology applications. Results indicate significant alterations in the physical properties of nanoparticles, particularly in saturation magnetization and Curie temperature, which are largely influenced by the changing coordination numbers of surface atoms. Furthermore, it is found that the anisotropic contributions from both the unperturbed volume and the surface layer substantially affect the magnetic behavior of the alloys studied. This research is supported by funding from the Basic Research Program of the Presidium of the Russian Academy of Sciences, acknowledging the foundational work in the design and application of advanced nanopowders in various fields.