Liquid Migration in the Paste as the Result of Consolidation

The processing of various powder materials is often done by an extrusion process; the powders being formed into a paste by the addition of a liquid substance. During extrusion, by reason of the extrusion pressure, some properties of the paste are changing, which affect its rheology and thus the extrusion itself. One of the phenomena is the movement of the liquid phase. This paper is focused on monitoring this phenomenon using model material in a simple test device. Its design simulates the effect of pressure in the extruder. The results of the measurements provide a picture of the movement of the liquid phase under the influence of the pressure in the porous skeleton formed by the powder material.