Summary: | A new general formulation of powder compaction mechanics based on continuum mechanics concepts is presented. The general governing equations are developed, and the analysis of both dynamic and quasi-static compaction of powders in cylindrical dies is presented. In the analysis a constitutive relation of isotropic viscous porous solid model for the powders, linear relation forms between strain and strain rates and modified mechanical properties relations similar to those developed in rock mechanics and geomechanics are used. Subsequently, the stresses and densities distributions throughout the compact including the friction conditions at any time are shown to be achieved. The preliminary results conducted on di-pac-sugar powder, uniaxially compacted at constant compression rates ranges from 10−4/s to 102/s, were encouraging. The theoretical models developed are in excellent agreement with the experimental data, particularly those obtained for densities and viscosities. The variation in both cases is found to be less than 5%.
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