Structure Formation of Magnetic Particles under Magnetic Fields toward Anisotropic Materials

Abstract

We performed numerical simulation of structure formation of magnetic particles under magnetic field toward anisotropic material development. In this study, we examined the unsteady process of the structure formation and its feature using magnetic particles with diameter of micrometers. This study evaluated the process of structure forming with various particle diameters and particle volume concentrations using the Non-dimensional Boundary Area (NBA). The structure formed by the magnetic particles does not depend on the particle diameter but depends on the particle volume concentration. In the case of particle volume concentration ϕ = 5 vol%, the bundle of chain-like cluster is not made and each chain-like cluster by magnetic particles is almost single chain. However, in the case of more than ϕ = 10 vol%, the bundle structure formed by contacts of multiple chain-like clusters is proceeding. On the process of structure formation by magnetic particles, firstly, the single particle rotates by itself with orienting the magnetic moment to the direction of the applied magnetic field. After then, particles connect with each other and the chain-like cluster is formed.