粉体の流動性に関する研究 (第7報)

ガラス玉に混和した粉体の流動性

抄録

Sliding angle and flow rate from an orifice were measured in a mixture of glass beads with lactose, anhydrous dibasic calcium phosphate, talc, titanium oxide, magnesium oxide, starch, calcium p-aminosalicylate (PAS-Ca), and calcium carbonate. In general, mixing of powders resulted in greater sliding angle and smaller flow velocity, and this tendency was especially marked in magnesium oxide, calcium carbonate, and PAS-Ca, and smaller in titanium oxide, talc, and starch. The degree of this change became greater as the diameter of granules decreased. Apparent specific volume of a mixture seemed to suggest that mixing of powders resulted in aggregation of glass beads and formation of some kind of an internal structure in the mixture. A correlation was found to exist between the value obtained from equation (2), which is thought to indicate the degree of aggregation, and the sliding angle and flow velocity. Therefore, changes in fluidity, as indicated by sliding angle and flow rate, by mixing of powders is thought to be due to aggregation caused by binding of glass beads themselves by mixed powders.