Magnetic manipulation of discontinuous ferromagnetic fibers in viscous fluids: Dynamics of single fiber alignment

Abstract The method of fiber morphology manipulation using magnetic field interaction is proposed for single discontinuous steel fibers dispersed in viscous fluids and subjected to low magnetic fields. The goal of this study was to investigate the fiber behavior under different test conditions. The effects of the fluid viscosity, the fiber aspect ratio and the strength of the magnetic field on the dynamics of fiber alignment were analyzed. In‐plane magnetic alignment tests with a single fiber were carried out to avoid fiber‐fiber interactions and fiber clustering. Based on the experimental results, a model to predict ferromagnetic fiber alignment caused by a static unidirectional magnetic field was provided. Existing models focus on the different torques occurring in the realignment process. The presented model is based on single‐term exponential equations and considers all previously mentioned variables. It is shown that a good agreement between experimental data and fiber realignment predictions for single fibers is achieved.