Experimental and computational investigation of the magnetic susceptibility of composite soft materials

Abstract

The magnetic properties of densely packed composite granular materials are strongly affected by interactions between the grains. This paper addresses the influence of the interactions, as a function of the packing density, on the initial susceptibility. Our calculations are based on systems with realistic physical microstructures which are free from an artificially imposed lattice. The introduction of particle elongation via demagnetizing factors due to prolate spheroids is shown to enhance the susceptibility and give results which are in good agreement with experimental observations of composite soft materials prepared by dispersing large Fe particles in a non-magnetic matrix.