EFFECT OF CHARACTERISTICS OF PLASTER MOLD ON THE SLIP CASTING OF HIGHCONCENTRATED ALUMINA SLURRY

Effect of suction pressure p(cap) and permeability K-m of plaster mold on the slip casting of a high concentrated alumina slurry of 58.8 vol % was investigated, Three cylindrical plaster molds were fabricated fr om 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 p(cap) and low K-m, high p( cap) and low K-m, and low p(cap) and high K-m, respectively. Casting r ate at an early stage increased with increasing p(cap) x K-m or K-m, a nd average bulk density of cast body increased with increasing p(cap) Local green density increased from the center toward the wall of mold because of consolidation of the compressible cake. High p(cap) x K-m a nd low p(cap) enhanced percolation effect, and resulted in remarkable segregation of fine particles near the mold wall, Green body with a hi gh relative density of 66.3% and a homogeneous density distribution wa s obtained from the 63%-mold showing high p(cap) and low K-m.