Fabrication of Strong Magnetic Micron-sized Supraparticles with Anisotropic Magnetic Properties for Magnetorheology
We propose three different techniques to synthesize anisotropic magnetic supraparticles for their incorporation in the formulation of magnetorheological fluids with novel potential applications. The techniques involve microtransfer molding, electrodeposition and microfluidic flow-focusing devices. Although the yield of these methods is not large, with them it is possible to synthesize supraparticles with anisotropy in both their magnetic content and shape. The magnetorheological characteristics (yield stress) of the resulting field-induced structures are computed using Finite Element Method simulations and demonstrated to be strongly dependent on the microstructural anisotropy of the supraparticles. In anisotropic particles, the simulated yield stress is always larger than the isotropic ones consisting of magnetically homogeneous spherical particles.