Densification behavior and attrition resistance of porous Al2O3 beads prepared by dripping-ice templating

Porous Al2O3 ceramic beads with a small-scale lamellar pore structure were prepared by the dripping-ice templating method. The densification behavior of lamellar walls and the attrition resistance of porous Al2O3 beads were investigated. For the two-dimensional structural lamellar walls, the intrinsic pores shrunk, and the necking area grew during the sintering process, leading to the densification of lamellar walls and the shrinking of porous beads. In addition, the two-dimensional lamellar walls and three-dimensional Al2O3 bulk are compared and possibilities of elaborating of the discrepancy in grain size and pore morphology are discussed. Attrition resistance was determined by a grinding test. The dominant attrition mechanism of porous Al2O3 beads is abrasion. High sintering temperature led to a decrease in the attrition rate due to a wider necking area and denser pore walls.