Effect of interparticle force on mixing and segregation of dry granular materials.

In this paper, the effects of interparticle force on mixing, segregation, and stratification in dry granular materials are investigated. Avalanche segregation, stratification and also segregation in rotating drums are examined. A series of binary mixtures of granular materials is prepared which consists of spherical iron particles and a nonmagnetic material. By placing each mixture in a magnetic field, the induced magnetic interparticle force could be altered and the effects on particle segregation observed. Using this technique, the effects of altering interparticle force on both avalanche and radial segregation are examined. It is found that altering interparticle force could induce mixed materials to segregate and also induce segregating granular materials to mix. We also report a complete reversal of segregation and stratification as interparticle force was increased. These results have important implications for the mixing of cohesive powders.