Compositional Variation in Multiphasic Compacted Powders

Abstract

For well mixed compacted powders such as those used in the Pharmaceutical and food industries, the assay variation in the composite particles is a bell shaped Gaussian curve with a mean assay of the bulk powder being compacted and a standard deviation proportional to the ratio of the powder to particle size raised to the 3/2 power divided by the volume fraction locked. With increasing compacted particle size, the standard deviation grows smaller. The Ferrara point, for these larger particles, becomes the peak of the Gaussian curve and differs in location from the Ferrara point of the smaller particles.