Abstract
The measurement of the tensile strength of powder bed has been carried out by means of the swing method measuring instrument, which has been developed by the authors.
It was evident that a displacement in a breakable section of powder bed appears as the tensile stress increases, then the stress displacement curves are obtaind respectively for each powder. These curves provide the energy required to the tensile breakage which may be correlated with practical particulate phenomena.
The most interesting problem is the application of the measurement of tensile strength for the design of powder equipment and material handling.
The floodability of fine material, which will indicate the tendency to liquidlike flow due to natural fluidization of a mass of particles by air, has been discussed empirically but theoretical bases are not sufficient on the evaluation of the potential floodability of fine material.
The dimensionless number deduced from our theoretical consideration is given by the following equation
Fc/mp·g=3·σ/(1-ε)dp·ρp·g
The ratio of the cohesive force affecting a single particle to a particle weight indicates a good correlation with empirical floodability evaluated by R. L. Carr's method.
