Analysis of the Magnetic properties in hard magnetic nanofibers compósite

The magnetic properties of the strontium hexaferrite nanoparticles were studied as they were embedded at different concentrations in poly(vinyl alcohol) (PVA) nano?bers. These nanoparticles were prepared using the Pechini method and a low frequency sonication process obtaining a 3.4 nm average diameter. The composite consisting of hard magnetic nanoparticles homogeneouslydispersed in a polymeric matrix was fabricated using a homemade electrospinning with 25 kV DC power supply. The obtained nano?bers had an average diameter of 110 nm, and nanoparticles were arranged and distributed within the nano?bers under the in?uence of a strong electric ?eld. The con?guration of the magnetic nanoparticles in the PVA nano?bers was such that the interparticle exchange interaction became negligible, while the magnetostatic interaction turned out predominant. The results reveal a considerable improvement in the energy product (BH) and in the squareness ratio (M r /M) for nanoparticle concentrations between 15 and 30% per gram ofPVA. The nanoparticles arrangement occurred at densities below the percolation concentration enhanced the hard-magnetic properties of the nano?bers, which indicates that the organization of the particles along the ?bers induces anisotropy from the magnetostatic interaction among themagnetic nanoparticles. Finally, we close the discussion analyzing the observed effect below the percolation threshold, where the induced anisotropy caused the reduction of the full-width at half-maximum of the switching ?eld distribution curves. Published by AIP Publishing.