Self-assembly of nanoparticles and flake powders by flake design strategy via dry particle coating

To achieve uniform dispersion of nanoparticles is an essential prerequisite to fully exhibit their enhancement effect in various composites. In this work, we propose an effective method to achieve the uniform dispersion of high content of nanoparticles in nanoflake powder by a flake design strategy through a dry particle coating method. It relies on the self-assembly of the nanoparticles on flake powders through mechanical forces when they are forced to pass through a narrow clearance during high-speed rotating. It is shown that uniform dispersion of 6 wt% TiO₂ nanoparticles on Al nanoflakes could be easily achieved after being processed at suitable condition. The DEM simulation results show that best dispersion occurs when the impact energy in both the normal and tangential direction is comparable, which provide effective collision to de-agglomerate the nanoparticles and attached them to nanoflakes.