Rheology of Powders. Part I. Flow Studies of Polystyrene Spheres and Saccharin Powder Through Glass Tubes. Part II. Bulk Tensile Strength and Shear Strength Studies on Saccharin Powder and Polystyrene Spheres

摘要

A study was conducted of the flow of polystyrene spheres of several particle sizes and of saccharin powder in glass tubes of various lengths and diameters. Polystyrene spheres were selected for study as a reference powder of known particle shape, and crystalline saccharin powder was selected as a representative crystalline material. The bulk tensile strength and shear strength of saccharin powder, and polystyrene spheres, both with or without additives, were compared. Additives to the powders in each instance were Cab-O-Sil and Arquad-2HT, a cationic surface active agent. The bulk tensile strength of saccharin powder without additives increased with compressive stress at a rate 27 times greater than that of the powder modified with additives. The shear strength increased with compressive load at a rate l.24 times greater for the untreated saccharin powder than for the powder modified by additives. The use of these additives with the polystyrene spheres had little effect, if any, on either the bulk tensile strength or shear strength.