Size distribution of a metallic polydispersion through capacitive measurements in a sedimentation experiment

We present a simple experimental technique to determine size distributions of metallic polydispersions. The particles are first suspended in a viscous fluid-like glycerol and then their sedimentation is followed by measuring the effective dielectric constant in a cylindrical cell at a fixed frequenc y. Thereafter, an inversion procedure of the data, based on the Maxwell-Gar nett effective medium theory and Stokes law, is used to directly obtain the size distribution. The technique is applied to three different stainless s teel dispersions and compares very well with a traditional sizing method ba sed in microphotography. (C) 2001 American Institute of Physics.