On the Scaling Law of the Pinning Force in MgB2 Superconducting Composites with Magnetic Nanoinclusions

Dense superconducting composites with magnetic nanoparticles were prepared by spark plasma sintering. In addition to structure and magnetic properties, we focused on the pinning properties as described by the field and temperature dependence of the scaled pinning force analyzed. We found that the pinning force does not obey any scaling law and attributed this effect to the anisotropy of the MgB₂ and the almost random distribution of the orientation of the superconducting grains within the polycrystalline sample.