Mechanism of plasticity development for ceramic dough (part 3) - Investigation of extruding characteristics and particle packing structure of the dough

The extruding characteristics and the packing structure of clay dough, and alumina dough mixed with water-soluble and water-insoluble plasticizers were investigated. The extrudability of the doughs, which were evaluated by the extruding pressure as a function of the packing ratio, became higher at higher volume of larger-sized pores reaching micrometed size. In the clay dough and the dough mixed with water-soluble plasticizers such as methylcellulose, the aggregates deformed into the larger-sized pores around each aggregate during extruding. In the dough mixed with water-insoluble plasticizers such as curdlan, the larger-sized pores based on curdlan gel, its deformation provided the fluidity of the particle. It was understood that the dough could be extruded by deformation of the aggregates or the gel acted as a buffer.