Notice of Retraction Nanoparticle control of slurry flow in microchannel

Abstract

We clarify the mechanism of the formation a free surface of slurry flow in a microchannel with a simple hydrodynamics model. A slurry is a solid-liquid and pseudoplastic fluid among non-Newtonian fluids [1, 2]. We investigate the free-surface formation of a slurry as a function of flow velocity. The shape of the free surface of the slurry is determined by the internal pressure, external pressure, and surface tension of the slurry. We focus here on the above mechanism and slurry particles, and propose and demonstrate magnetic field gradient control of free-surface formation. First, we demonstrate that the free surface of a single magnetic slurry consisting of Fe3O4 nanoparticles and an organic solvent can be deformed by a magnetic field gradient. Next, we demonstrate the control of the free-surface formation of a nonmagnetic ceramic slurry under a magnetic field gradient by adding a magnetic slurry. With this means of controlling the free-surface formation of slurry flow, we can completely fill microstructured molds with slurries. This can lead to defect-free compacts with microstructured shapes.