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arXiv · 0802.3416

Fractal Substructure of a Nanopowder

Thomas Schwager·Dietrich E. Wolf·Thorsten Poeschel
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Abstract

The structural evolution of a nano-powder by repeated dispersion and settling can lead to characteristic fractal substructures. This is shown by numerical simulations of a two-dimensional model agglomerate of adhesive rigid particles. The agglomerate is cut into fragments of a characteristic size l, which then are settling under gravity. Repeating this procedure converges to a loosely packed structure, the properties of which are investigated: a) The final packing density is independent of the initialization, b) the short-range correlation function is independent of the fragment size, c) the structure is fractal up to the fragmentation scale l with a fractal dimension close to 1.7, and d) the relaxation time increases linearly with l.

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Thomas Schwager, Dietrich E. Wolf, Thorsten Poeschel. 2008-02-25. Fractal Substructure of a Nanopowder. https://doi.org/10.1103/physrevlett.100.218002

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