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arXiv · 1704.01565

Charging changes contact composition in binary sphere packings

Andre Schella·Simon Weis·Matthias Schroeter
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Abstract

Equal volume mixtures of small and large polytetrafluorethylene (PTFE) spheres are shaken in an atmosphere of controlled humidity which allows to also control their tribo-charging. We find that the contact numbers are charge-dependent: as the charge density of the beads increases, the number of same-type contacts decreases and the number of opposite-type contacts increases. This change is not caused by a global segregation of the sample. Hence, tribo-charging can be a way to tune the local composition of a granular material.

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Andre Schella, Simon Weis, Matthias Schroeter. 2017-05-11. Charging changes contact composition in binary sphere packings. https://doi.org/10.1103/physreve.95.062903

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