Effect of Suspension State on the Pore Structure of Freeze‐Cast Ceramics

The forming process of a freeze‐cast pore structure and the packing state of ceramic particles have been studied from a colloid point of view. Several typical alumina suspensions with different dispersion states are prepared by controlling the dispersant amount and the pH value. Microstructures of the samples freeze‐cast and sintered from the suspension were observed. It is found that the interaction states of the particles in suspension have a dramatic influence on both the packing state in the dense region and the structures of channels. The results also indicate that the short‐range interactions among the particles are a crucial factor for the pore structure.