Publications Details

Applied mechanics modeling of granulated ceramic powder compaction

Mahoney, F.M.

In ceramic manufacturing processes such as dry-pressing, correlations between applied compacting pressure and resultant powder compact density are essential for defining reliable process conditions for ceramic components. Pressure-density diagrams have been developed as a tool for both process control and for understanding the compaction behavior of different powders. These types of diagrams, however, pertain only to the average properties of a powder compact and do not address a significant issue in powder compaction processes: the formation of density gradients within the compact. Continuum-based mechanics models of varying complexity have addressed the influence of frictional forces acting at the powder-die wall interface which dissipate the applied pressure throughout the compact. Resulting pressure distribution models are then typically coupled with empirical functions relating pressure and density to obtain a green density distribution in the compact. All of these models predict similar trends; however, none predict the distribution with sufficient accuracy to be considered as a design tool for industrial applications.