Effect of suction pressure pcap and permeability Km of plaster mold on the slip casting of a high concentrated alumina slurry of 58.8vol% was investigated. Three cylindrical plaster molds were fabricated from the slurries having water-to-plaster mass ratios of 0.55, 0.63 and 1, and designated as the 55%-mold, 63%-mold and 100%-mold. The 55%, 63% and 100%-molds were characterized by low pcap and low Km, high pcap and low Km, and low pcap and high Km, respectively. Casting rate at an early stage increased with increasing pcap×Km or Km, and average bulk density of cast body increased with increasing pcap. Local green density increased from the center toward the wall of mold because of consolidation of the compressible cake. High pcap×Km and low pcap enhanced percolation effect, and resulted in remarkable segregation of fine particles near the mold wall. Green body with a high relative density of 66.3% and a homogeneous density distribution was obtained from the 63%-mold showing high pcap and low Km.
