Self-assembly of ferromagnetic particles into chains and spin under the control of traveling magnetic field

In this paper, the spin phenomenon of self-assembly of ferromagnetic particles to form particle chains under the action of a traveling magnetic field (TMF) is investigated, and a TMF generator is designed and fabricated to experimentally observe the self-assembly and spin phenomenon of ferromagnetic particles under the action of TMF. The TMF generator is capable of generating a TMF, which is an alternating motion magnetic field with sinusoidally varying and translating magnetic induction, under the action of which a chain of self-assembled ferromagnetic particles is subjected to an alternating magnetic force thereby generating a spin motion. By analyzing the spin mechanism of the self-assembled ferromagnetic particle chain, the relationship between the rotational velocity of the spin motion of the particle chain and the frequency of the three-phase AC power supply of the TMF generator was obtained. Adjusting the frequency of the three-phase AC power supply of the TMF generator can control the spin velocity of the particle chain. TMF generator enable ferromagnetic particles to self-assemble to form particle chains and drive the particle chains to spin controllably, which has a wide range of applications in micro-robotics, biomedicine, and microfluidics.